exhausted

I stopped selling avon in 2017. two years later around oct 2019 i received a call from an agent from the above mentioned collections agency, mind you i have never received a call sms or even an email from anyone from avon prior to all of this. I set up a payment arrangement where i would pay R200 per month. I started paying december 2019 and i would still get calls from the agents from shapiro requesting the full amount. i made 3 payments of 200 and there system was never updated and i got tired of paying as i saw no sense in doing so. I have been trying to get assistance with my account since april 2020 and to date no1 was able to help all i hear is we waiting for feedback from the client, i sent emails on numerous occasions with very little feedback.