Apple watch data plan transfer

[Crunchypants]

I received my new Apple Watch 7 today, it is an upgrade on my previous 5.

Last week I paid of the remaining contract on the 5 and took out a new data plan for the 7.

When I try to add the data plan to watch it sees the plan and asks me if I want to transfer it to the watch, I then get an error and it tells me to contact O2 and quote reference code 94, I have tried this on 3 occasions now and none of the operators had a clue what to do, one of them even transferred me to Apple and they checked the phone and said it was an O2 problem and told me to contact them.

The watch is fine, it syncs ok with my iPhone 12 it just wont take the data plan.

[MI5]

You'll need to call customer service on Monday and asked to be transferred to the watch team.
Numbers here Guide: Coronavirus Community Help and Support 
When it comes to the reason you are calling stay silent for 15 seconds and you will be taken to the keypad options.
Press 2 for Everything Else
Press 5 for More Options
Press 7 for Anything Else which will put you though to someone.
Say "Upgrade", "Lost/Stolen" or "Fraud" if you have to, to get put through to someone.
8.00am is the best time to call if you can.

[Crunchypants]

Have sussed out what the problem is I think. The data plan it shows me and asks if I want to transfer it to this watch has the EID number for the old watch, the EID number for the new watch does not show.

I'm reluctant to chose the "buy a new data plan for this watch" option because the upgrade came with a new data plan and I don't want to be stuck with 2, is it possible that the new data plan hasn't been activated yet because of the weekend or do I need to still try Customer Services again in the morning

[Crunchypants]

an update on this

I have now spoken to 12 different people regarding this, including Customer Services, in store people, live chats with an O2 "Guru" and had 2 call backs from an O2 "expert" and am now being told that I have to wait for another Guru to contact me.

It seems that we all know the problem now (or so they say) the old watch data plan has not been cancelled when I upgraded, so the phone is still trying to add the old data plan which doesn't exist because it has been upgraded to the new one, but the new one doesn't exist (other than in MyO2 billing) because the old one hasn't been deleted.

Yep, you've got it, you are just as confused as I am.

I am fed up with going around in circles, I want someone to do actually something, I have told them that if it doesn't get sorted next time they contact me I will be returning the watch, I am still within my 14 day change your mind period