Swap sim

[Charlie55]

I have swapped to a 5 g sim but the account has not been upgraded and i cannot access the phone. This was an hour ago

[Bambino · Accepted solution]

@Charlie55 Did you follow this guide: SIM Swap: a mini guide (incl eSim) - O2 Community

Have you turned your phone off and back on again?

If you're still having problems you can reach O2 via social media:
Facebook (https://o2uk.co/O2CFB), Twitter (https://o2uk.co/O2CTW), or Instagram (https://o2uk.co/O2CIG)
Or you can call them on 0800 081 0255

You can use Skype to call if you have no working phone: Guide: A Guide to Skype 

[MI5]

@Charlie55 

Keep rebooting.

The process can take up to 24 hours but usually much quicker.