SSDA Demands without Documentation

About 6 months ago I started receiving phone calls & SMS's from SSDA with regards to an outstanding MTN account for my husband stating that we have to pay R349 now. Until this time we had not received an account, statement or any form of correspondence from anyone with regards to an outstanding MTN account. My husband has been unemployed for over 3 years and as such MTN would never give him a contract, so my husband requested a copy of the contract and has continued to make this request for the past 6 months. Some of the call centre staff have taken our email address, but some just put the phone down on you. If you request to speak to a supervisor or team leader you are told "No, they are not available". To date we have not received a copy of the contract and as such I refuse to pay it. I have told them I would like to see what a judge has to say about them not providing a copy of the contract, after all nobody in their right mind is just going to pay an account that they are not aware of. the manner in which they conduct business is a disgrace.