Unauthorised debit order retrieval fiaasco by MTN

On 30/11/2024 an amount of R8997.14 was withdrawn from my cheque account. The amount was credited to debicheck MTN SPBA *** I reported it to FNB on 02/12/2024 Despite numerous attempts to retrieve the amount from my FNB account, and very confusing multiple-choice options on an unhelpful MTN site, I was assured the amount would be rectified within 6 weeks. To date ... zilch!