Whenever I go abroad, T-mobile phone and text service works but there's no data connection. The phone connects to the networks, there's 3G or LTE sign but no data.
I am on iPhone 6S (previously 5), latest software and the same issue happened in September in Peru and Bolivia and now in Mexico.
I have reset the Network Settings, made sure Data Roaming is on, send text to #767# to make sure the international data is on.
Every time I call the T-mobile customer service, they set up a ticket but no one has provided a solution; the engineer calls you back in 3 days but there's no solution; after a few days, you just give up and fly back home where service works fine and you forget about the issue.
I heard that this could be related to APN settings; Apple does not allow APN changes so the phone is set to IPv6 and many towers do not support it.
Has anyone found a solution? besides buying a non-Apple smart phone?