New set up and SIM card not working

Hi I have just received my new SIM card. I have inserted it into my old handset pixel 6a if that matters. I have the signal strength icon but no data showing and can't make phone calls. I have checked the phone is unlatched from O2 (it is). I have checked APN name etc and all seems ok.
Any ideas why it isn't working?

I would advise contacting customer support for help with this issue KellyW1 as it sounds like something has gone wrong with the porting process.