Roaming in USA number not recognized

[rukfrus]

Spoiler

Roaming in USA on PayGo with Google Pixel 6 unlocked, connected to T-mobile LTE. Incoming calls get a "number not recognized" message, outgoing calls work fine. SMS and data both work. If I connect to AT&T, which is what the SIM wants to do, incoming calls get the message "the person you are calling is on another line, please leave a message blah, blah, blah."  Spent the morning with tier-two network support, they finally suggested I use Whatsapp. I don't think my elderly relatives will go for it 🙂   

[PeteG]

Hey, Rukfrus.

Welcome to the Three Community. 

That's quite a strange issue to be running into. Your number should generally always be recognized, even when the phone is off or not connected to any networks. I'm not sure what would cause that, and in most cases I'd normally advise to get the person who's calling you to double check the number they are calling, but I'm guessing you've already tried that. 

When on AT&T, calls need to be made over 4G LTE since they removed their 3G network. If someone is calling you and not getting through, it might be because VoLTE isn't on. Can you head into the settings for your Three SIM and make sure that option is enabled and try again? 

It might also be worth turning off wi-fi calling during your checks to make sure the phone isn't trying to use wifi calling while abroad, as this can stop calls from working properly.

I hope you manage to figure the issue out 🙂 

Pete.

[rukfrus]

Hi PeteG, thanks for the suggestions.

It appears the Google enabled VoLTE roaming for "many US and global carriers" with the update to Android 13 on the Pixel 6a. My handset is running Android 13, however, the IMS service status shows IMS Registration as "Not Registered" and Voice over LTE as "Not Available."

If I put my SIM in a friend's Pixel 4a running Android 13 everything works as expected. So, I'm inclined to think that either Google's fix for VoLTE roaming is broken on the Pixel 6a, or there's a provisioning issue for this particular handset on 3's end. I've contacted Google Pixel support and sent them a debug log from my handset. Can you advise on how to directly contact 3's network support without having to go through lower tier support with whom I've already had a two-hour chat without any resolution? Thanks.   

[StephR]

Hi @rukfrus, thanks for coming back with these further details.

The SIM working fine in your friend's Pixel 4a would seem to suggest it's not a provisioning issue, but we're checking this out for you with some of our tech contacts.

Can you please let us know exactly what software version and security update level you're running?
Have Google come back to you with an update or any suggestions?

StephR

[rukfrus]

Hi @StephR thanks for getting this checked out. My phone is running Android 13 with the August 5,2022 security update. My friend's phone is also running Android 13 with the same security update. The difference between these handsets is that the Pixel 4a uses a Qualcomm modem while the Pixel 6a uses the newer Tensor chip. I'm still working with Google to find a resolution.

[hd]

Did you find a resolution either with google or three? Was you phone bought unlocked? I'm wondering if this is an issue where the phones were bought untied to any network.