You can reschedule your appointment using the Comcast online appointments scheduler or using a phone to talk to a real person from Comcast by dialling (800) 934-6489. Comcast enables you to have your appointment online from the comfort of your office or home or at any of its physical locations. You will receive an electronic confirmation for your Comcast appointment after you’ve completed the process to the email address or to the phone number that you have provided during this process.