Bad customer service

This month August I phoned foneyam asking for an arrangement for my monthly payment, where by I have also asked the consultant that I have a wish to pay off my contract before the time and she also told me the balance, then call cutted us off I called again I found another then we made a monthly arrangement then after I received an sms asking if I want to cancel the contract I refused where by I have a proof,then when the arrangement date arrived I went straight to my @pay on my capitec to make payment so usually the amount is always programmed so I only press pay again,so I did after I got a message that I paid R1200 instead of R316 I phoned capitec and foneyam to ask why this happened, then capitec explained that the amount was changed from foneyam, so I went on to request my refund through the manager called Samantha all she was doing was empty promises and lies till today,I gave her a proof and explanation and she also listened to recordings and just today after promising me lies she then telling me that I won't get my refund meaning they forcing me to pay off by force.