I have been in the USA for about 2 months, previously my SIM was working for phone calls and texts (I disabled roaming data on the phone, as I don’t need it).
Recently it has stopped working - it shows no signal everywhere, and cannot join any mobile networks. Previously it automatically joined AT&T - now they are all marked “forbidden”. I have tried using the SIM in a different phone, which shows the same problem. That other phone works for a different UK SIM from another network, so I am pretty sure that my iD SIM card is at fault.
My account is paid up. International and Roaming features are both still On. Are there any additional troubleshooting steps I can try?