Dual-SIM phone setup

[MissMyBike]

To manage data use in Mexico, I converted my Verizon physical SIM to eSIM on my dual-SIM mobile phone. It works fine, here in the US, with no physical SIM cards in the phone. I had a physical Movistar SIM card, which I placed into the phone, hoping I'd see the phone recognizing it, & walk me through the setup. No such luck. The phone doesn't see the physical SIM card. I am guessing, the issue is that I am in the US & should be in Mexico for the SIM to be recognized for further setup. Does anyone have any experience with this process to provide some tips?

[DonJuane]

Have never been a Verizon customer but if venturing a guess, the conversion of the phone to eSIM would (if thinking logically) disable the reading of a "physical SIM" when one is inserted but you'd have to speak to a Verizon expert who understands the features of your phone model to figure that out. Also I don't know how MoviStar "roams" and who they partner with in the USA and if it that partner provides LTE as one of MoviStar roaming customer's choices or not. In contrast, if roaming with MoviStar in the US only provides the capability of GSM at 3G speeds then it would be logical that a Verizon based phone would not support MoviStar in the US because phones made for Verizon use LTE for 4G and then default back to the old CDMA/EV-DO for 3G/2G service. If MoviStar only partners with 3G GSM/HSPA+ companies in the US such as T-Moibile and AT&T, that means you'd be out of luck with a Verizon phone that focuses primarily on providing LTE for 4G and then falls back to the old CDMA/EV-DO protocol for 3G and lower (instead of GSM/HSPA+). And I would assume the Verizon phone you have now will not be able to communicate on the GSM/HSPA+ bands that AT&T and T-Mobile use but that would all depend on the particular phone's features.

If you are saying that this particular Verizon phone worked at one time with a MoviStar chip while in Mexico, the only thing I can figure out is that perhaps your Verizon phone was communicating with a MoviStar LTE tower in Mexico that was using a LTE frequency that a typical Verizon LTE phone supports. And it could also be the reason the phone won't work with a MoviStar SIM chip in the USA is for certain any LTE partner for MoviStar in the USA would be using different bands and perhaps the LTE partner band in the USA is not Verizon and thus one that this Verizon phone doesn't support. So there are many situations which could cause the setup not to work. It's also entirely possible that there is simply no LTE service provided at all for roaming MoviStar customers in the USA and if that's the situation, it may be that only 3G speed service is available to those customers. If it is indeed only 3G/2G support then since the default 3G/2G service for MoviStar in Mexico is GSM/HSPA+, that would demand a roaming GSM customer be forced to use a GSM/HSPA+ capable phone in the USA and if that is indeed the situation, that would mean you'd need a GMS/HSPA+ 3G/2G phone which would include only unlocked phones designated originally to support 3G/2G GSM/HSPA+ which would include in the USA only T-Mobile or AT&T because Verizon phones when forced into 3G service go to their previous protocol which is CDMA/ED-VO and there are no phones I am familiar with that can default down to 3G using either/or CDMA/ED-VO or GSM/HSPA+, so it's pretty much set that while 4G LTE is only restricted by which model phones support which LTE bands, when any phone has to "fall back" to 3G/2G then the phone will typically if a Verizon phone fall back to CDMA/ED-VO protocol and fall back to GSM/HSPA+ protocol if MoviStar, TelMex, T-Mobile or AT&T (e.g. NOT Verizon.)

To see if MoviStar roams to LTE in the US, it might be worth trying the MoviStar SIM card in a phone that's LTE capable and has been unlocked and originally provisioned to AT&T or T Mobile in order to check if the card is still active and then if it connects to a partner US network's LTE service or if it just defaults to 3G/2G (indicating MoviStar only utilizes GSM/HSPA+ when in the USA). If the test LTE phone does connect to a LTE partner with the named LTE connection showing active on the screen (e.g. connected to T-Mobile or AT&T LTE or even Verizon LTE) then that would indicate a strong possibility that the issue of your SIM not working is completely caused by converting from SIM to eSIM. On the other hand if you see the MoviStar chip placed in the test phone only utilize a 3G/2G partner's network and it ignores the LTE capability that T-Mobile or AT&T based phone is capable of, then you can assume that MoviStar only provides 3G/2G service in the US and thus requires a phone which defaults to GSM/HSPA+ for 3G/2G and not CDMA/EV-DO for 3G/2G like a LTE Verizon phone will. Now that's my educated guess as to what the issue is.

**** this article says that MoviStar partners with AT&T which would mean the Verizon phone in the US would need to access either an AT&T LTE band or have a fallback to AT&T's GSM/HSPA+ network in order for MoviStar to roam into the US, which I am assuming that your Verizon LTE and CDMA/EV-DO 3G/2G backup will not help you attain. https://www.capacitymedia.com/articles/3...astructure Still I think I'd start with getting rid of the eSIM and going back to hard SIM cards if that's an option for you.

Otherwise ir you wish to summon further opinions you might try posting this over on the Chapala group. They seem the best at worming their way through "the matrix" and if anyone has made a path, usually one of them has cut that path or is not too far behind the one "who's cutting one" ;-) .

https://www.chapala.com/wwwboard/webboard.html

**** Updated this post to include extended syntax for CDMA/ED-VO 2G/3G architecture (Verizon) and GSM/EDGE/HSPA+ 2G/3G architecture (AT&T, T-Mobile, MoviStar, Telcel, etc.)

[DonJuane]

Here's some additional info I found for you. I'm always behind technology wise using phones because my spending limit is normally $50 US or a little more, as most of my phones end up shattered on the sidewalk, in the toilet or in someone else's pocket. Nothing I've owned does the "eSIM" trick. Also I never go out walking in Mexico with anything in my pocket I can't live without.

https://www.verizon.com/support/dual-sim...s/#devices

[DonJuane]

This is a little humorous reading the Verizon page about eSIM operation. I wonder if they have not ever heard of BLU and other Chinese Android phone mfgs. with the dual SIM slot feature that have been on the market and sold in many different models for nearly a decade. Still their eSIM solution does answer the difficulty of supporting dual SIMs in a single SIM chip phone and thus provides dual carrier support without actually requiring dual SIM slots. Still it does guarantee that they'll be the only provider at least on one-side of any future dual carrier setup. And did you catch the part that stated how unfortunately they could not provide eSIM capability if Verizon had supplied the subject phone (how convenient LOL).

I guess if you are Apple and don't want to change your overall look and feel and you are listening to your customers like the growing number of people who travel and require more than one country plan, this is the only logical way to implement this, as adding a "real" additional SIM slot might not make the grade of the suave aesthetics required to maintain the status of their expensive phone model line.

Anyway from what I've read from the link I shared it sounds like inserting a MoviStar SIM as a second provider in the "physical SIM" slot should give you service but very likely only if Verizon is a partner with MoviStar, which it very well may not be so since the link I provided states that AT&T is the US affiliate. If it's AT&T, it would just come down to the LTE bands that the phone you have supports and if in addition to the Verizon LTE bands, the particular phone you have supports any AT&T LTE bands. And if 4G is not even an option for MoviStar roaming in the USA and 3G is all there is available as far as roaming, then unless that Apple 11 or whatever phone you have supports both CDMA for Verizon but additionally GSM for other standard providers, then MoviStar with only CDMA protocol towers available will not work on a CDMA-only Verizon provisioned phone. Again one would have to look over the phone specs to see what the phone is capable of. None I have seen to date do both CDMA and GSM for 3G activity but I haven't even seen an Apple 11, much less read the spec sheet yet.

Now in contrast to all this, you may be seeing a LTE connection for the physical SIM chip on the Verizon phone that MoviStar had requisitioned. If this is the case, a fix to gain access may be as simple as defining the proper ATN data in the phone configuration for SIM card via the phone settings and this info can normally be found online, but then you'd likely need to use either the ATN data defined for MoviStar of Mexico or if that doesn't work, the ATN data provided by AT&T for MoviStar when roaming in the US. Search for (perhaps) "MoviStar US roaming ATN data". But this is only if you see a LTE signal indicated for your physical SIM chip and the phone still won't provide connection.

[DonJuane]

The Apple 11 sold in N. America looks like it will cover just about everything:
Cellular and Wireless

Model A2111*

FDD‑LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 29, 30, 66, 71)
TD‑LTE (Bands 34, 38, 39, 40, 41, 42, 46, 48)
CDMA EV‑DO Rev. A (800, 1900 MHz)
UMTS/HSPA+/DC‑HSDPA (850, 900, 1700/2100, 1900, 2100 MHz)
GSM/EDGE (850, 900, 1800, 1900 MHz)

All models

Gigabit-class LTE with 2x2 MIMO and LAA4
802.11ax Wi‑Fi 6 with 2x2 MIMO
Bluetooth 5.0 wireless technology
Ultra Wideband chip for spatial awareness5
NFC with reader mode
Express Cards with power reserve

The LTE bands would handle 4G for respective carriers that use the band, all carriers would fit in this range and use sub-set of named bands
The CDMA and EV-DO would handle Verizon 3G
HSPA, HSDPA would handle AT&T & T-Mobile 3G (MoviStar Mexico & Telcel Mexico roaming 3G)
GSM/EDGE would handle AT&T & T-Mobile 2G (MoviStar Mexico & Telcel Mexico roaming 2G)

So if you have an Apple 11 and can't use your MoviStar SIM in it, it looks like a configuration issue.

[DonJuane]

Of course left open is how the software handles what the hardware "can do if enabled". There's always the chance that Apple set up where the owning or primary carrier can control what overall features are usable in the phone and it's very well possible that Verizon "provisioning" (subsidy paid phone) could turn off the HSDPA and EDGE (GSM based 3G & 2G) since Verizon only uses ED-VO & CDMA for 3G & 2G) so now on second thought, the fact that a phone has all these capabilities doesn't mean they are all active and available at any time and it means that a carrier, especially if you bought the phone from the carrier, might have some of these features locked out if in fact the software simply wouldn't support it (running several technology pieces of hardware at the same time). Also if not to kill the potential of competition, which most of the locking and lock-out is the purpose of this, it also could be a power issue. Lithium battery technology can only go so far and Apple "hand computers" with their growing need for more power and their processing and features grow, it could very well be built into the Apple OS (operating system) that no two technologies could be working at the same time due to power consumption issues. Now this is only speculation but makes sense. Also if you add this to the fact that this whole eSIM thing is a new technology is pushing a system designed for a single-SIM originally to do acrobatics so to speak, then it's entirely possible that the eSIM/SIM dual carrier software is not smart enough to have the phone function is such two different architectures (old GSM vs CDMA) at exactly the same time.

So we've talked ourselves "all the way back to go" now, and we discover there are many, many reasons why this might not work and even though hardware-wise it's equipped (outside of the dual drain on battery of course), it may very well not be supported software-wise, particularly where the eSIM takes the phone down the old CDMA route and the physical SIM takes it down the old GSM route. In short the phone even if it was equipped to handle both vastly different technologies at the the same time, for battery drain reasons you might not even want to do that, especially in the situation of these new super tech phones that won't last a day on a single charge using a single set of hardware transmitting technologies.

At this point you'll likely need to seek out a large Verizon store, as online or phone support help may be hard to find. You'll need to talk through this whole eSIM software with them and see what it supports at the same time an if indeed the software can address all radios and technologies the phone is capable of at the same time. Just be sure to tell them that the extra physical SIM you are inserting is off a GSM/HSPA 3G based provider so they will know what they are dealing with. Good luck!

[DonJuane]

OK, looks like I guessed it right if your phone is an iPhone 11 and you are on iOS13:

https://support.apple.com/en-us/HT209044

To use two different carriers, your iPhone must be unlocked. Otherwise, both plans must be from the same carrier. If a CDMA carrier provides your first SIM, your second SIM won't support CDMA. Contact your carrier for more information.

If you have an enterprise or corporate cellular service plan, check with your company administrator to see if they support this feature.

So for this reason if you are a Version customer and go the eSIM route, this locks the phone to two numbers from the same carrier.

*** POST UPDATED: After re-reading Apple help website.

It appears that the dual SIM feature only benefits customers who want two Verizon lines/numbers. To do the country switch if you want two SIMs you will need to go to a phone such as BLU with two actual SIM card slots and then they will need to be either the Verizon CDMA style of phone or the "Rest of the World" GSM style of phone. So going with Verizon would logically limit the sharing of SIM cards in "lesser capable" or "designed for one architecture" phones. In the case of the Apple 11, I'm betting the only solution is to go back to an actual physical SIM and then pop "out" the Verizon and "in" the MoviStar SIM when you are in Mexico and perhaps put the Verizon SIM in a dedicated Verizon inexpensive phone you stick in your back pocket or keep on the dresser.

[DonJuane]

Re-reading again, it looks like the service should be dissimilar and it SHOULD work. Wow, how confusing. I'd follow Apple and consult with Verizon to see what can be done in reality. Again specify that the MoviStar is GSM for 2G/3G and they partner with AT&T in the US for roaming. If you don't mind, let me know what they say.

[MissMyBike]

Thanks Don for his extensive response & advice. Here is the latest:

I was able to add $100 MXN to the balance of the Mexican SIM card while in the US, & then tried it in an older iPhone 6. The phone recognized the SIM card & I was able to call a Mexican number from US. Then I figured I should retry it in the iPhone XR (which has been functioning on the Verizon eSIM with the physical SIM card slot empty). This time, I tried the process by first powering the phone down before loading the Mexican SIM. Once powered up, the phone woke up to "Activation Required". This was a new development, as previously the phone did not react to the new SIM. Not knowing whether going through "Activation" would zap the eSIM, I aborted the process. The phone said, because the "primary" carrier is unavailable, it'll use the "secondary" to use the contacts. This was new too. I think powering it down before SIM insertion made it recognize the SIM as primary (which is different from what Verizon had said when setting up the eSIM - Verizon had said the eSIM would be my "primary"). So I posted the situation to Apple Communities, on whether going through "Activation" will zap my eSIM setup, rendering my phone useless in US. Once I am convinced my eSIM setup won't be affected, I'll proceed with activation of the physical SIM. No answer yet, but once I know, I'll provide an update.

[MissMyBike]

Update: I got a response on Apple Communities, indicating that proceeding with Activation process would not zap my eSIM. So I went through the steps & the physical SIM is functional. The process was somewhat convoluted & seemed to crash a time or two, but at the end, I noticed the SIM & eSIM were both working.