Panic over !!
I did something (don't ask me what) but I got a "save" button appear top right. I saved and was then able to go into general settings and find the advanced settings and continue from there, so all done for now, until the next Q's
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion.
This is not Customer Service so we are unable to help with account specific issues.Currently using:
Pixel 7a (O2 & Lyca), One Plus 6 (Sfr), iPhone 12 Pro Max (Vodafone)