Not responding to Disputes

I have lodged a dispute in regards to accounts being listed on my ITC report and was told that this will be rectified within 20 working days, this is now more than 20 working days and again after two more dispute attempts where I am still sitting with the exact same problem. Prescribed accounts not yet removed nor updated. Default listings for an account that is paid in full and closed is still listed as open and unpaid on my ITC report. Several other accounts that was paid and settled are also still listed as unpaid even after proof was submitted. Default listings are being removed and then re-listed again. Accounts vanish and then reappear, how is this even possible? My credit score is not being shown on my ITC report for several days now, please can someone look into this matter.