IPad Air 4 cellular not working
Hi,
I have a new iPad Air 4th gen. with Wifi and Cellular.
I have a sim card fitted, but it doesn't seem to work. I've tried turning on and off again; the network is briefly searched for, then is disappears and there is nothing next to the Wifi signal symbol.
I've checked that mobile / cellular data is on, tried resetting the iPad, taking the sim out and reinserting it - it recognises that it's there, as I'm asked (and am successful) to enter the pin.
What else should I check?
iPad Air, iPadOS 14