Still unhappy with Vodacom service!!

Vodacom has again sent me a statement I know nothing of, and threatening to block my line if I don’t pay. Since the last reconnection my quality of signal has been very poor, I don’t know what they did, and now they say I owe them more money. Vodacom! What is it that I am paying for? I did not subscribe to anything, in fact I asked you to cancel everything that you claimed I was subscribed to. Paid you the money! What do you want from me!!!