Taking my money for nothing in return

My contract ended last year, September, but they keep deducting money from my account. I've phoned numerous times to cancel. I've got a reference number and everything. Yet, they STILL take my money.

This reminds me of the time I bought a phone from them and when I had software issues, they told me I bought the phone from a black market. Even though I had an invoice proving otherwise.

They are *******. Nothing else.