on 15-01-2021 18:39
on 15-01-2021 18:46
Discount schemes here Guide: O2 Open & Friends and Family discounts - How to sign up
If it was an O2 customer services loyalty you would need to call and see if they would re-add it.
on 15-01-2021 18:47
Simple answer is that you can't
You will have to apply for it again
If it was given by the upgrade team it doesn't mean they will give you a loyalty discount again
If it was a discount scheme then look at this link
Guide: O2 Open & Friends and Family discounts - How to sign up