What is the Xfinity/Comcast customer service email for cable internet customers?

Since your chatbot is literally worthless & doesn't answer my questions, putting me into a chatbot loop, & the Xfinity app is broken when trying to access several key functions, & trying to discuss these issues over the phone results in repeated aggressive, high-pressure "upgrade" sales pitches, is there a contact email for Xfinity/Comcast so I can get concise & accurate answers in writing to these & other similar questions? 

“Is NOW100 available to my exact address at $30/month all-in, including unlimited data, taxes, fees, and the required gateway?”
“Can I retain my current Xfinity Internet until the NOW Gateway is received and proven working, and how will the pending Voice-removal credit be handled after conversion?”
“Does NOW Internet require a credit/debit/prepaid card on file for auto-renewal, or do you require ACH bank-account autopay?”
“On what exact date will my first $30 payment be charged, and what dates of service does it cover?”
“What record will show my renewal charges, and how can I download it for my own files?”