Bad service

We had a loan with Absa that was handed over to Brooks and Luyt attorneys, the load was settled on the 18th December 2020 until today we keep receiving calls from them we need to pay. As soon as we provide the id nr they say the account has been paid off we then ask for a paid up letter as now we can't take another loan the bank says we still owe money they say they will email immediately well we are still waiting after asking twice. These people will call day and night abd they do not deliver any services now I need feedback or this case will be taken further this is terrible services cannot believe Absa Bank such a big company will do business with such bad service delivery. I will br awaiting feedback on this matter urgently.