Iphone not working

[Sophie9]

New iPhone old sim

[Sophie9]

Upgraded to iPhone xr from Samsung cannot except or make calls

[Cleoriff]

@Sophie9 

You need to contact O2 and ask for iData to be provisioned on your account.

Guide: Coronavirus Community Help and Support 

[KingAmo]

@Sophie9

Have you make sure that the SIM is properly inserted?
Restart your phone several time to see if it works.

If it doesn't use the SIM in another phone to see if this problem can be solved.

When did you upgrade?

If none of the above then I'm afraid you have to call customer service.
https://community.o2.co.uk/t5/Other-Products-and-Services/Coronavirus-Covid-19-Community-Help-and-Su...

[jonsie]

Use your old sim for the time being and do a sim swap when things settle down @Sophie9