I recently upgraded my IPhone to a newer version and bought a new SIM I changed them over fine but it’s been over 24hrs now and I still can’t make or receive calls? I have tried removing the SIM and putting it back in again but that doesn’t seem to work
Did you ask for a new sim when your upgraded? as if so this should already be activated. If you didn't and it just arrived with one there is a chance your old one is still working and you will need to complete the sim swap process.