Bad service from Telkom

Telkom service is pathetic... I over paid an account that was handed over to a collection company. After realizing that the account was fully paid and that collection company is still taking money from me I approached them and asked for a refund... They said that only telkom can reimburse me. I have since been waiting for my refund from October 2023. I have sent numerous emails, made numerous phone calls... I was asked on numerous occasions to send through bank statements and identification but still nothing. I honestly have given up now.... It's costing me money trying to get my money back. Thank you