Complaints going unanswered

I acquired a new MTN contract on 26/10/2017 where I signed and accepted the terms and conditions of the contract and associated RICA/FICA conditions. Since purchasing the contract from MTN the number given to me has been useless as it is constantly bombarded with debt collectors. I contacted my legal advisor, who advised me to complain to MTN as this should not be my problem to resolve and in not providing the service I pay for MTN is in breach of contract. I have contacted MTN directly to arrange for a sim swap or something but no solution is forthcoming from MTN as I have had contact with Charelle Brockhampton and Thobekile Mkhize.