Being charged a different (much higher) price from quote

I recently updated my internet service with a new 1 year term to Gigabit Xfinity Flex Service ($75/month) with $10 per month in discounts (paperless and mobile customer).

I was given a summary both during check-out and via email indicating that my monthly bill (after discounts) would be $65 per month.

Now I have received my bill for the first full month, and it was for $99 - a $10 discount from a price of $109.

If I log in to my account and choose "change plan" it shows me that my current plan costs $65/month. But this is not reflected in what I am being billed.

It seems to be impossible to contact a human customer support agent and the automated message system just talks in circles - so this "error" is becoming quite infuriating.