*****ed R690 refund by telkom

Telkom is a *****ster of a company.I have been paying for my data and the last payment was done in october but they kept deducting without sending me a statement to confirm how much is left all to find out I have finished paying this router in october and they said they will refund me the balance of R690 within 72 hours and the 72 hours ended last week Friday on the 2nd February ubtil today I havent received my money, instead they sent me an invoice saying I owe them R251that I dont even know what is it for. I have been trying to call them with no response for 30 mins am holding a line. Thay have poor service and *****ing people their money.