Close my contract

Hello MTN beware!beware! Of the wifi router or data contracts even the contract recharges...i have been experiencing problems this contract it is so unreliable this is what happened: I recieved a call before my contract with MTN ended of which it was only left with 6months to end ..okay the called and asked me to if i wanted to upgrade ...top up or to continue with their contract recharges,so i continue with the contract ..therefore this contract was supposed to end 3years back but now MTN keeps on deducting money from my account claiming that the contract has renewed for the next 2years....the simcard is no longer there i don't use the data...as the Owners of the network i believe they should have seen that i haven't been using the data all along for about 3years what hurts the most is that they are deducting money from my account saying that i owe them WHEN THEY WANT TO THREATEN ME WITH LAWYERS THEY MAKE A PLAN TO GET HOLD OF ME...BUT WHEN I WANT TO CANCEL SINCE THEY SAID IT IS CONTINUING BECAUSE I DID NOT CANCEL ,THEY PUT ME ON HOLD FOR HOURS ...sometimes i call the help line then they refer me to the help line when i tell them i tried to wait for the contractors on the phone they give me attitude and tell me "THAT'S THE PROCESS THAT'S HOW THEY WORK" am very disappointed...at their service....they are unreliable....Please help cancel this contract i don't want it anymore i am tired of it now