Roaming in USA

[scotties]

Hi, I'm in the USA and having issues connecting to any service. Have been able to connect intermittently but only for sketchy data, SMS and phone calls not working. Tried resetting APN settings but now stuck with wrong settings and no data service either. Checked phone compatibility and that's ok. huawei p30 pro. Tried all the troubleshooting. Tried getting setting sent to SIM from site but not received. Looking at apn settings the MCC which should be 234 but is set to 240 and MNC is set to 07 instead of 57. When I change them and save I can see they revert when I checked. All the mms settings are locked with same wrong configuration. Is there a way to unlock these settings. Thanks

[scotties]

I'm still getting intermittent mobile data connectivity but no phone or SMS.  Need to authorise some logins but can't do it.

Tried the sky menu abroad setting several times but no success.

Really frustrating,  my wife's phone is having exactly same issue which is a Samsung s21+ so must be a sky/local network issue.