Extremely Dissappointing Service

Extremely Disappointing service. I have been trying to cancel my dsl service with them since july and its October already. They keep taking my money, I have been to their shop 4 times already. They keep telling me that I owe them money, which I have proven with supporting documents that the money went off from my account, yet on their side they cannot allocate it. Absolutely terrible service... its astonishing actually.