****mers want to collect again on a closed account

My Finchoice account was handed over to them in the year 2020 then they called me gave me the settlement discount from amount debt of R10 000 they sent the settlement letter with discount to settle the account with amount of R6700 then I settled the account in the month of September, and they sent me the paid-up letter and the account was even removed from my ITC profile.

Today they send me SMSes to say I must settle my Finchoice account with amount of R1300 after full 3 years. Just because I lost the paid up letter they sent me they think they can call me after full 3 years to collet again on an account that was closed. Saya please fix this mess and I want that paid up letter again of Finchoice account because it was issued from you guys you still have my records, and I'll be calling NCR to let them know about the ******ion your company is doing.