Overpayment refund(Subscription)

I overpaid multichoice R4000 while paying my January 2022 subscription using the FNB banking app. I went to FNB to request assistance with reversal on the same day: 31 January 2022 and was referred to Wonderpark Multichoice because the bank is not allowed to reverse money from public recipients' accounnts. I was promised that I should expect the refund in eight working days, after submission of the required proof of payment and copy of ID, however money was not refunded . I went to do follow-up, but still promise not fulfilled. I decided to call Multichoice and was told to submit same documents I have submitted to Multichoice centre that I visited. Follow up done, but till today I am not getting the refund. Please hepl I am stuck.