no answer at 808 no help from mtn stores

i have been trying to cancel contracts since Feb. Nobody answers 808 they just cut you off. I did not take the upgrade and had it sent back because how would you activate your upgrade ? I tried calling 808 while personnel of rtt newcastle witnessed no surprise no answer tried three times. The problem is they are billing me on contracts that have run the 24months but how can you cancel them if MTN 808 or MTN refuse assistance. They are now charging me more on a laptop that is paid off and sim cards that are not used than they did during the contract period. How does this work you take money and play it so you cannot be contacted bet MTN make millions this way so be Warned