O2

I’ve just upgraded to an iPhone 12. Everything is set up, transferred everything from my old phone, but my new phone won’t let me make calls . Any ideas ?

My device contract ran out august 2020. I continued with a data/ text / minutes plan etc for 18 months. However , I decided to upgrade my phone . I’ve just realised that I now might be hit with two bills every month, or will my new contract take plac...