Contract pricing is not being honored by Xfinity

My Xfinity internet and cable TV bill increased this month by $70.00. I have a contract in place that guarantees pricing for two years. I have the email transcript from the agreement from last year. I have tried both chat and phone customer service with no help from either. Because this contract pricing is legal and was agreed upon I expect Xfinity to honor it. If no resolution can be made than I will be forced to escalate to the Indiana Public Utilities Commission for assistance. As a 24-year Xfinity Diamond Member and a Honorably Discharged Disabled Veteran on a fixed income, it is disappointing that you would increase a persons bill by $70.00 without contacting them and explaining the rational for the increase. Thank you.