Error code 112

[Lobby]

I'm trying to add an Apple watch to my pay monthly plan but I get error code 112 each time I try and a notice to call O2.  I've tried several times but the support has been non-existent, with them telling me to call Apple as I bought both the phone and the watch from them.

I know from other posts that this isn't an Apple issue and likely needs a configuration update by O2.  Is anyone from O2 able to help?

I've checked the usual things like wifi calling being enabled and everything seems to be correct there.  Both devices have been restarted but that didn't help either.

[MI5]

@Lobby 

It has been reported that this works:

Go to Settings >Mobile Service.
Scroll down to 'Apps by usage' and turn OFF 'Watch'.
Go back to the Watch app on your phone and go through the mobile plan set up again. .
Turn 'Watch' back on in Settings >Mobile Service.

[Lobby]

Thanks for the suggestion.  I have tried that and it has not worked.  I have also spent more than an hour on the O2 help and after talking to 4 different people, resetting the watch and repairing they have admitted that they do not know how to resolve error code 112 and have been using google to try and help.  They suggest i go to an apple store or O2 store and see if they can help.

I am surprised it is proving to be so difficult - is this normal?!?

[MI5]

Literally hundreds of posts with the same issues on here @Lobby 

So yes it's normal but clearly not acceptable.