Filing a complaint

Xfinity is quite a disappointment. I am a new customer, so my complaint is about how customers are treated, rather than the internet service at this time. I agreed to have my account drafted so I could get a discount on my bill. I, just like many others live on a budget. I just received my first bill and was charged a larger dollar amount for my first month's service. When I spoke with a xfinity representative about this, I was informed that the change on my plan had been made a couple of days after service started, so I would have to pay the larger dollar amount for the entire month! REALLY??? Then I was told to contact the government {???} to file a complaint because they were responsible for taxes and fees. HUH??? We weren't discussing taxes and fees. We were discussing the larger charge on my bill. The representative had no interest in helping me. He was simply earning a paycheck. If I do not receive a refund for the dollar difference on my first month's bill, I will not recommend xfinity to anyone. This is not how customers should be treated.