Been on T-Mobile prepaid since 2015. Spent much time in Europe but normally have a local number AND the US sim in a dual sim phone. Basically using the prepaid credit to text and receive OTPs and the occasional call. Never used data roaming nor do I want to (have local sim for that). This trip, arrived to Greece and never had a problem before, now the sim will not register on any network. It’s been like two weeks. Talked to support and they said everything is fine and I should have coverage. I have no coverage whatsoever. Tried sim in multiple phone (including an iPhone 11), still no luck getting it to connect. Manually searched for networks and they all say “forbidden”

Any ideas?