Letter of demand for a Paid up account

Account was under debt review since 2019. I received a paid up letter that it was paid in full in 2021 fast forward to Jan 2024 when I was done with debt review. You have handed me over for an account that was paid up. Easton Berry attorneys (Meloshini N)sent the letter of demand for R323.32, which I rep**** and attached a paid up letter. They were contacted by Debt Rescue as well to update that it was paid in full. How can you hand a account over that was paid up in 2021? It's 2024....? Trust me when I say I will NOT be opening an account anytime soon with you again.