Got billed for a phone i never sent for repairs.

Last month my account was debited for an amount higher than my normal monthly subscription. On enquirying they told me that my phone went in for repairs. Apparently my phone was ****** more than a year ago so i am not in possession of that cellphone. They promised to credit my account 3 weeks ago. I called Autopage again this morning without any joy, the consultants and accounts dont have the faintest idea of what is going on, eventually disconnecting my call.