12-01-2017 00:56 - edited 12-01-2017 01:02
Hi @Anonymous Welcome to the forum. You should be able to change tariff via My O2 http://www.o2.co.uk/myo2
If you have any problems then ring customer services in the morning http://www.o2.co.uk/contactus
Between 8-8.30am is the best time...
When you go into My O2 have a look at the left hand side of the first page. This is where you can change tariff
on 12-01-2017 06:34
OnePlus 6 (O2 & Sfr), Z3 Tablet (Three UK), iPhone 8+ (EE)