Cancellation of service

We have logged several calls asking to cancel <br> At first wanted to charge R2000.00 for providing Internet ar R90.00 per month<br> Have asked for copy of contract, to date have not received one<br> Received a call today - account is now over R4000.00<br> Say we bought headphones of R2500.00<br> Still the difference does not equate to these type of charges<br> Really tired of this continuous bad service<br> We need proof of contract and purchases