Canceled contract and double billing

I have had no joy with these people in the two years I have been with them. On numerous occasions I have been double billed. I have been harassed for the last month buy there agents wanting to re new my contract or offer me anotber contract. I contacted there call center a few weeks ago to confirm that my contract was over and debit orders will stop going off my account. To my surprise another payment went off my account this morning. I want someone to contact me about this as this is unacceptable. You can contact me about this on ********** 001.