MTN what the hell?

I am trying to cancel a contract that is more than 10 years old. I sent a cellphone in for repairs, went to pick it up and the store moved. I neber got the cellphone back but i have been debited all this time. I decided to settle a balance earlier in the year and i asked for the co teact to be canceled but to no avail. This was in February. Fast forward im again in arrears with MTN, again i settle to balance and all i want to do IS CANCEL THE DAMN CONTRACT but i can't because on 4 occasions now i wait 30 minutes+ to be transferred to the collections department and THE CALL CUTS. As a pensioner im at my wits end.