I rang O2 Customer Services for a PAC Code as i'm moving to BT Mobile however when i type in the PAC Code on the BT site it comes up isn't correct as it has no letters all numbers, but i didn't hear any letters when O2 gave me the code.

Are you sure you didn't get a PUK or handset network unlock code?

02's PAC follows this format: TEL123456

You've been given a PUK; not a PAC. PACs always have three letters and then six numbers after.

Went to the O2 shop in my Town & it's now sorted out.