MartinL

I used the app. for a while and liked it but they updated it to only use iOS 13 and above. I'm not that modern so it was back to SMSs.

I also tried changing SIM to my wife's phone. My phone is Apple, my wife's phone is Samsung. Still didn't receive OTP.

I've had this problem for over a week - phone service is AIS. I enter Gateway ID and password, get a message saying OTP has been sent - the partial phone number is correct - but it never arrives. On my phone, origin of OTP messages was a Thai phone number "+66 89 304 0043". I phoned HMRC who said they'd had many similar complaints but everything was correct at their end. E-mailed AIS who were very good in their response. They said SMS messages had arrived from senders "BIG3G" and "SSB_PROD" at about the times I requested OTP. Those senders seem to bear no relation to Government Gateway or HMRC. Ultimately, though, AIS couldn't solve the problem. Late yesterday, I tried to get OTP again - same problem. Just before writing this, I tried yet again, expecting the same problem again. BUT THE OTP ARRIVED INSTANTLY!! This time the origin of the OTP was "NXSMS" rather than the Thai number. Looks like it was an HMRC problem all along. I suspect the OTP system was undergoing a change but the call centre operators weren't aware of it. I wonder how much stick they got from callers because the OTP department didn't keep them informed.