I recently accidentally purchased a supposed comedy movie, I have not and would not watch the movie! How do I cancel these accidental purchases and deletete the movie?????
If an employee doesn't help you here, contact one of their Billing reps at the phone number on your bill or 1-800-Comcast, chat with them using one of the "Account and Bill" options at https://support.xfinity.com/chat, or visit a Service Center if one is nearby (check locations and hours at http://www.xfinity.com/support/service-center-locations/) and have them reverse the charge.
In addition to getting the billing corrected, consider setting up a Purchase Pin on each of your cable boxes/DVRs to prevent this from happening. See https://www.xfinity.com/support/articles/how-to-block-purchase-of-pay-per-view and/or https://www.xfinity.com/support/articles/x1-parental-controls-turn-puchase-protection-on-off.