Blacklisted for Unrealistic Maintenance Costs

I am very much disappointed in I.H.S property management, it happened that I was renting an apartment at Centurion in Molware estate sometime last year from 1 April to 27 October 2019, so I cancel my lease and I received the move out report of the issues that pin point the things which I found them not fixed when I moved in which I was billed R4657. 50 for maintenance costs. So I explained everything to accounts consultant and also attached the move in and move out report in the emails to support my statement. I was advised to dispute the matter with *** and Property Manager who said he will investigate and revert back to me on the 13/11/2019, which he never did. I wrote follow up emails but never bothered to come back to me, until I got the SMS yesterday on the 03/08/2020 that I am blacklisted by IHS to my surprise I am still waiting the feedback from the building manager. And how can I be blacklisted without proper communication that based from Property Manager investigation I must settle the account? They mentioned that I must call for information, I called numerous time still the lady who is accountable for the blacklisted issues her phone goes on voicemail since yesterday.