Do you mean incoming or outgoing calls @Rodders1959 ?
If incoming, you can't.
Outgoing you can either submit a SAR (see if this helps Requesting your personal data from O2 | Help & Support | O2 ) or download all your bills and piece it together yourself.
Guide: How do I get to the 'Download Bill' page?
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 Do not publish personal details (email, phone number, bank account).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
