Std Bank Cheque account closed but now owing again???

My Std Bank Prestige account is apparently in arrears and that account was closed in 2015 . Now i am getting calls from MBD that Iam owing the account and it needs to be paid. The ladie that called was so rude and insensitive on the phone.

The person who was handling my accounts in my time of unemployment was my late mother who passed on in October 2017. So how do i retrieve records or payment for someone that died????

I think that standard bank needs to look carefully at the records for this account because my hands are tied now. I hope to fix and solve this query as soon as possible..