Cell c non existing service

I was a contract customer went over to prepaid and 3 weeks ago ported to another service provider because of no service from Cell C. They have blacklisted me for an account that nobody can tell me how where or when. I’ve contacted MBD which they handed me over to and no success either. I have spent R600 on airtime to try and contact them to sort it out and all I get is eish sorry sir we can’t help you. I have ref nr from accounts, legal department , collections and nothing. They just sign them of a day later without any solution or the numbers don’t exsist. Meantime I can’t get a contract from new service provider as I’m blacklisted by cell c. You can’t even speak to the original people so names don’t matter cause they all work from home and can’t be connected. When you eventually do talk to a consultant as soon as they don’t know what to say they drop the call. I’m beyond myself and are preparing to take my firearm and go to head office and threaten them until the matter is solved.