International roaming / India - has issues

I have had this same problem. When I landed in New Delhi airport on July 1, 2022, it kinda worked, though slow, but that is expected. I have spent the last few days in Guwahati, a pretty large city. Apart from the inability to get to the internet, I have another problem: the data service rarely works, including texts. This is a severe problem for me as whenever I try to make a purchase using my US credit cards they send a code in a text to my registered phone number for verification. But since I don't receive these texts (except sometimes with a random delay that can last hours, by which time the purchase is timed out), I cannot use my credit cards. All the while, my phone shows LTE with 50% bars (with an R on top to indicate roaming, and the Settings show that the SIM is now registered to "vi India"). Strangely, occasionally it works great; I have even had a video call once through Whatsapp with a person in the US.

After reading this forum I decided it’s not worth my time to talk to T mobile about connection issues; they are clearly aware of it but decided not to do anything about it.