Cannot text or call since returning from abroad

I went on vacation to Spain and on return to UK I cannot seem to receive or make calls or text, iMessage is ok.

I recall receiving a carrier update which I'm wondering messed something up.

I've tried resetting network settings, enabling airplane mode, switching off, leaving for 5 mins, removing sim, but to no avail.

Comparing the screen to my daughter 5, her circles next to carrier seem to be filled whereas mine don't

Any ideas?

Thanks

Please give the specs for your iPhone and carrier so one of our UK members can assist you. Thanks...

It's on o2 and an iPhone 5s 16gb

Did you change SIMs before you left, or after you arrived in Spain? A Spanish SIM would be an easy explanation, with an even more obvious fix: put back your UK SIM.

It's possible your Spanish provider somehow overwrote your O2 carrier file, but a visit to your O2 provider (avoid resellers, go straight to a carrier-owned store) should be able to clear that up. In short, sounds like the SIM in bunged.

Same SIM, if I place my giffgaff sims in it does the same, my SIM in theirs is fine.

Is this device jailbroken or unlocked? How was that done if it was done?

Ok, looks like the unit has developed a fault. My sim works fine in other units but none of my other sims work in the 5s so it's on its way back to Apple. Thanks for the assistance Chas, don't think anything was going to sort this apart from Apple.