I have received many quires about comcast email not working. So, facing issues in any technical platform is not a big deal but first you have to understand the reason why you are having issues. Read mentioned below reasons:
Poor internet connection
Incorrect configuration settings
Your daily sending or receiving emails limit exceeded
Recipient address is incorrect
Read also: https://riich.me/blogs/view/5372
https://ityug247.hpage.com/simple-steps-to-fix-comcast-email-not-working-issues.html
https://ityug.wordpress.com/2021/04/21/why-is-my-comcast-email-not-working/
https://rewardbloggers.com/blog/post/24808/how-to-fix-comcast-email-issues