Recurring account issues

I recently had my account closed with Telkom and handed in my device has there was no coverage in my area. Everything was agreed with info given to me that i will get a small amount of money back. I now received a statement that i owe them an amount in excess of R5000 rands. I have given back the device when we had reached an agreement that the account will be closed due to they are in the process of building a reception tower and this will take 2 to 3 years. For how long do i have to deal with problems i thought were resolved?<br> <br> I have escalated this through the call center also (New Case Number ***1)<br> Please immediately rectify this has to show Zero as this is unacceptable, and the reason I left Telkom due to this type of service<br>