MTN complaint: Refuse to Refund My Money

Good day im allana lategan and my complaint about Mtn is that i have cancelled my data contract with them on 13 December 2022 and paid the cancellation fee.The Mtn Callcentre gave me the amount of R400 to cancell my data contract but when i arrived at a Mtn branch i was put on the telephone with the mtn callcentre again and a different amount was given whereby i had to pay R1400 everything included but when i contacted the mtn callcentre again just to make sure i do not owe them anything the consultant explain to me i overpaid mtn and that im eligible for a refund of R1085.I have been trying to contact mtn from December 2022 to resolve this refund and everytime mtn will email or contact me saying in the next 5 days my refund will reflect in my bank account but nothing like that happend until today 20230207 when i contact mtn again and there reply was my cancellation cannot be found and why they are deducting from the refund they owe me starting from January 2023