@AngusOgg
After it's been enabled you need to reboot your phone to get the options.
They may be under network, sim or call settings, depending on phone and firmware.
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)