Installation appointment, no confirmation

I went through the steps to schedule an installation appointment, but when I finished the process I was sent back to the xfinity homepage and have not received any sort of confirmation. Trying to log in to my account (using several browsers) just results in an infinite loop. The xfinity app says I have logged in successfully but shows only an "Access not Authorized" message. There is no apparent way to contact customer support on the website.

How can I determine if my installation appointment was successfully scheduled or see anything about my account?