International roaming blocked permenantly by the system when the international pass is still valid

I bought a 30-day international pass for a 3-week business travel in Asia. 2 weeks in I received a text message from T-Mobile saying that my primary usage in the last several months has been international which is against their terms. As a result I'll lose all the international data when my pass is expired. I did travel a lot for work this year, but I used local wifi most of the time so that I didn't use much roaming data from the international pass. So I called the customer service for explanation but they can't really help. I've been a long time T-Mobile user and have been traveling a lot internationally for work for the last couple years. Such thing has never happened to me even when I was abroad for 6 months in a row. On the day my pass expired, I did lose all the international data which essentially turned my phone into a dead brick without wifi. It was super annoying and I called T-Mobile multiple times during my travel but none of them can solve the problem including the supervisor. Today I got confirmation from another so-called supervisor who said there's nothing they can do to change it. Basically blaming me for traveling too much! I have to travel abroad again for work in 3 weeks. Since they are incapable of solving the problem, that means they're telling me they don't want my business. So I'm going to have to switch, but if you also travel overseas a lot like me, I'd strongly advise you to avoid T-Mobile at all cost if you don't want to feel lost and have unnecessary troubles when you're abroad.