In france and having problems with T-Mobile one. I realize I am limited to 3G speeds but I keep having to restart my iPhone 7 to get onto Orange 3 G network to get internet access. It seems particularly bad after I have been on a Wi-Fi network - after leaving WiFi range the phone refuses to rejoin the 3G network without the restart.
I don't know what's causing your issue getting on the network but there seems to be some confusion about the network speed. You are not limited to the 3G network. You have access to LTE. Your speed is throttled by T-Mobile to either about 128 kbps or 256 kbps depending on if you have One or One Plus. They call this either "2G speed" or "3G speed" which seems to confuse a lot of people.
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