Did you report it lost. If not you would be liable for any calls and data used
Reporting it lost also gets you a replacement SIM with the same number
Guide: Lost or Stolen O2 Device? - How to Report it
You will have to speak to O2 to see if they can do what you want
Guide: How to find help & contact O2
This is not O2 and we are all customers here similar to yourself and cannot answer account type queries.
