HANDING OVER ACCOUNT AFTER NO HEADS UP

I do have a personal loan with Nedbank. I was retrenched in 2021 after getting Covid and spending 2 months in the ICU at Millpark. Currently on 24 hour oxygen as well as CPAP. I have made an arrangement with them that I would pay them R300 per month until the Credit Card is settled then I will increase to R500 per month. Now I keep on getting threatening messages from Nedbank and a Company called Norton Lambrianos Attorneys. According to Nedbank my account was never handed over to them so why am I getting sms from them with regards to this account. I have paid you EVERY MONTH. I have not missed one month. If this is how you treat you Customers you won't have any left after a few years. I am deeply disappointed in NEDBANK.