Numbers coming in incorreclty - showing as foreign countries

I was having the same problem for months and just fixed it using what @jorfanakos wrote and it worked:

If you check under 'phone' in setting (iPhone users), the 'My Number' probably has a + in front of your phone number. I tried removing the + by re-entering my phone number and it would not accept the change.

So I looked further down where it say 'Show my caller ID" and clicked on it. What I did was turn it OFF, wait 2 seconds and then turn it ON again.

Then you return to the phone page and you should see the + is gone from you phone number when looking at the 'My Number'.

Et Voila! 😊

Hope this helps!

I think I figured out what's happening (in my case, at least).

I'm international (Spain) and have the $50 15GB add-on, so I'm calling back to the US a decent amount. My friends told me that when I call them it comes from a Russian number, so I asked for a screenshot which revealed a lot. My US number is in the 720 area code. Russia's intl country code is 7, evidently.

When I call then from Spain, T-mobile knows that I'm international, so they format it accordingly by adding a +. But they appear to not know that I'm dialing using a US phone, so they don't add the +1 (just the +). Therefore, the recipient's phone sees +7 and formats it as a Russian number.

¡Hola, @w053lxl​!

Welcome to our Support Community! Boy, do you have an interesting issue going on. Thanks for already trying the hard reset. It's likely a setting within the phone. Which iPhone are you using? Do you have a T-Mobile SIM inserted in the phone? Are you within the US when trying to call the numbers shown? Lastly, when this started a week ago, was this after a software update or did you change any settings? I'll do my best to help get to the bottom of this!

iPhone X, yes it’s a T-Mobile sim and no changes at all to Software or settings

>

Thanks for coming back to let us know what type of phone you're using! Amanda had a few other questions as well if you have a sec to fill us in:

Do you have a T-Mobile SIM inserted in the phone? Are you within the US when trying to call the numbers shown? Lastly, when this started a week ago, was this after a software update or did you change any settings? I'll do my best to help get to the bottom of this!

¡Gracias! 😊

I share exactly the same problem. Started 2 weeks ago after a T-mobile carrier up-date. My boss lives in Wisconsin and has a 920 area code. He is in my telephone book but he gets not recognized and it shows the call comes from +92 Pakistan. I even got a marketing message from T-Mobile telling that they are adding more countries to my international plan... I live in New Hampshire, area code 603 / +60 is Malaysia. Very annoying.

iPhone 7s / ~1,5 years old never had an issue before.

Whoa, that is odd @magenta1536507​! Thanks for providing the additional info!
I know we sent marketing messages about our recent changes to the Simple Global country list to many folks, so I don't believe that's related although the timing is super awkward. I am really curious about the fact that your phone is suddenly recognizing numbers you've had stored for ages as international numbers, though.
Although it seems the OP is using an iOS as well, we haven't seen a ton of action regarding this in our Community yet. Can you double check the country format in your contacts using these steps: iCloud: Change the country format for iCloud Contacts 

Sorry to hear you are also having issues with this. What is your current software version?

My iPhone runs IOS 11.4.1

Thanks for looking into this.

Sven

Sent from my iPhone

Do you store domestic numbers as +1920-xxx-xxxx etc.?  IOW, put  a "+1" before the area code in stored numbers and see what happens.