Unacceptable poor service

I had a personal loan at FNB which was fully paid and a paid letter was sent on the 5th of January 2023. On the 25th there was an amount deducted which I reported to an agent who said they will escalate this and get back to me. I have not heard anything to date, so I called again to find out there is no escalation recorded. This is unacceptable and the service is absolutely of poor quality. FNB's service has deteriorated over the last year and I no longer want to be a client of theirs!!