Double billing for internet

Being charged twice a month for internet bit customer service tells me Im not. ITS ON MY BANK STATEMENT AND THE MONEY LEAVES MY ACCOUNT. I've been dealing with these charges for 3 months now. No one at xfinity wants to help. Im so fed up, im going to my bank this week and doing charge backs for the unexplained charges that dont show on any billing statement. Anyone else deal with this? How did you get it resolved if you did??