Cannot extend the ringing before voicemail is applied.

[Shas]

I want the ringing ro ke more then it is atm because voicemail has answered? I have tried the code that has been given but I get a message to contact  customer services. Ant ideas?

[pgn]

All done in your MyO2 these days, using the web version, @Shas - under Divert Calls.

https://accounts.o2.co.uk/signin

Good luck!