Can't make or receive calls

[LuuVigorito]

My iphone 6 has suddenly stopped receiving or making any calls. When I try and ring someone it says call failed and when someone tries to ring me it goes straight to voicemail. It won't even let me listen to my voicemails that people have left me. Any help?

[BandOfBrothers]

Is this happening in one place or everywhere ?

If one place check your masts. 

If everywhere reset the iPhone. 

On the iPhone hold down the Sleep/Wake Button and Home button together until the Apple Logo shows. Then On seeing this Apple Logo release both buttons ,and the iPhone will reset , which has been known to clear most glitches.

Settings -> General-> Reset -> Reset Network Settings.

Try your sim in another phone if this fails if you can to rule out the SIM card at fault or the phone. 

Check with Live Chat from a Pc or 191 that their are no issues with your account. 

[pierogas]

Having the same issue (iPhone 5C) which only started today -have tried all the usual steps as above but no luck - all software and carrier software is up to date.

[kids]

If when you tried your sim in a different phone and the problem persisted you will need to go to a Vodafone store and ask them for a new sim.

They will be able to transfer all you account details and activate the sim while you are instore.