Misrepresentarion and service failure. (clearance certificate)

I have been with OCTOGEN since 2016 and have paid all my creditors and just need the form 19(clearance certificate). Prior to paying my last creditor's balance, A lady called me and I asked her if the outstanding balance of my creditor was settled, would I be issued with the clearance certificate. She stated the only thing I needed to do was to pay the creditors' outstanding balance and my certificate would be issued in three week's time. Now octogen send me a bill of 6800 as their fees payable prior to issuing the clearance certificate. I have been at loggerheads with this company trying to resolve this matter.

Jan 2022= Sadik from collections promises to escalate the matter. Feb 2022= No phone call. May 2022= Bernadade from collections also promises to escalate to Karen. Nothing gets done. 16 May 2022, Sadik from collections calls me and states that I am liable for their fees as I signed the contract in 2016. My question is why did Tebogo(collections) state that after paying my last creditor, they would issue the certificate. OCTOGEN is a nightmare of a debt company to deal with. They never contact you as per their promise and their client service is atrocious. Can you cancel these fees due to misrepresentation as well as service failure on their end.