Poor service

If I could give FNB a minus I would have. I had two loans with them and I paid both in 2018. Since last week I've been receiving emails and sms text that I still owe R829 for the second account which was apparently not closed though paid off. I've contacted them last week since Monday and finally got through to someone that could assist on Thursday. The lady took my details down and said she will request for the account to be closed. I'm still receiving sms's and then I contacted them again on Monday for the whole week I have to hold for about 30 to 40 minutes before I get through, as if that is not enough they transfer me from department to department until I run out of airtime without being assisted. FNB's service sucks and their customer experience is not up to standard. This account is affecting my credit score very badly. I want this account closed as a matter of urgency. Furthermore, what the hell do I have to do in order to get assistance. I will never ever recommend anyone to FNB