my Samsung galaxy s4keeps telling me my sim is unavailable

[beckshope]

I had a Samsung s3 phone and then was given a Samsung s4 phone, and therefore transferred my sim from one phone to the other. I had no previous problems with the SIM card in the S3 and all my contacts ( in google account anyway) have transferred correctly to the S4. Also I have no problem making or receiving calls.

However, intermittently, the phone tells the sim is unavailable and I need to restart the phone. This happens in the middle of phone calls when the call just cuts out. It also happens when using the phone for Internet use.

usually if I restart the phone the connection is restored without me having to physically reposition the sim, and it does look well fixed within the SIM card holder.

i have tried taking the sim put and pushing back in and cleaning the surface of the sim but none has made a difference. Can you tell me if this is a problem with the phone itself, or the sim, or the connection or registration of the sim, and how to solve this please?

thank you Rebecca 

[BandOfBrothers]

Hi @beckshope

Process of elimination: Can you try you're Sim card in another phone to rule out either the Sim or Account or Phone which may be at fault. 

And again try another sim in your phone to see if it still happens. 

Any Vodafone store can replace your sim via a Sim Swap. 

You could try a factory reset after creating a backup to preserve your data in the phones storage and remove any Sd Card to prevent that being accidentally re formatted. 

If that does not help I would look to Samsung Support. 

Find a Service Centre  Here

and or use Samsung Uk Support  Here

[Annie_N]

Sometimes a SIM just doesn't seem to work 100% in a different phone. Presumably there is some very minor flaw in the SIM, which is picked up by one phone, although not by other phones. If you have convenient access to a Vodafone store, getting them to swap your number and account to a brand new SIM may well be your best first step.