MTN ********** ended being Blacklisted

Please assist I'm now blacklisted because of MTN, I have ********** contract at MTN which I don't know, I tried to go to different branches and head office I'm not getting any help I even send an affidavit and a copy of ID still no reply. My life is blocked I can't do anything because of this contract. I wanted to take a loan to buy building materials for my mom I'm blacklisted at the age of 27. Please assist I don't know what to do anymore.