Fosprops Richards Bay review: False billing

2019 I got retrenched so I went to Fosprops Richards bay to pay my levies.

I paid the current debt and 1 year ahead meaning I paid for 2020 upfront. Now I am selling my property to my surprise I learned that I've got a debt of 2017 which I knew nothing about. I do not understand where this debt was all along. now I am forced to pay it even if I do not agree with it. because if I do not pay I am not receiving my levy clearance certificate (from Fosprops) which is delaying the transfer process. I am not getting a reasonable explanation and I really feel oppression from Fosprops. They tell me I was on arrears of about R2700 in 2017 I do not which month, and Stilus their attorney paid those arrears and now with interest it is at R20000 and more. Including the tenant noise fines I must pay R36000 in other for me to get levy clearance certificate.