Unfortunately o2 are pretty bad at doing call backs @annoyed7 .
Have you tried contacting o2 via social media (if you have them)?
If you message O2 on Facebook (https://o2uk.co/O2CFB) , Twitter (https://o2uk.co/O2CTW) or Instagram (https://o2uk.co/O2CIG) , they should be able to help you with this.
Please note, this is not customer services and we cannot access your account. Do not publish personal details (email, phone number, bank account).
Link to our guide on how to contact them can be found here
