EDGARS - Harrassing me a year after account was fully paid and closed

Yesterday I receive a call from some debt collector telling me that I owe Edgars! Imagine my surprise when I closed my account with Edgars A YEAR AGO!!!! I went to Edgars (a year ago!!) asked the cashier what my balance was, told her that I am paying the FULL amount (It was an amount over R 7,000.00, which I paid from my FNB debit card, THE INK ON THE RECEIPT VANISHES AFTER A WHILE!) and that I am CLOSING the account!!!! She was on the phone for a while with accounts, I imagine, and I also requested a PAID UP LETTER!! To date, I have not received anything (I put it down to the fact that everyone is on a "GO-SLOWER" mode, using the lockdown as an excuse!!! When I check my Clearscore record, Edgars also pops up AGAIN!!!! Edgars, surely you have the technology to process a FULL PAYMENT and CLOSE an account??!!!

This debt collector person then tells ME that I have to GO to Edgars to clear this!! I have to use MY RESOURCES to PROVE that I have PAID you???? Surely you can do better, EDGARS!!!