Demon Internet

Despite closing my Demon Broadband account as normal in June, due to poor service, and despite 3 further calls to Demon Customer Services, all promising that no further payments will be taken from my CC, Demon continue to debit my CC by £22.99 per month. They now owe me in excess of £100. My CC company cannot do anything to resolve this & All I get is empty promises from their call centre saying it’s fixed, last conversation wwas a virtual stand up fight with them denying they are still taking my money & me (with my CC statements in front of me)insisting they are. Needless to say, every Demon number I try routes me to yet another call centre person who promises to resolve it or denies there's a problem & nothing gets done