Personal email blocked from sending to comcast.net

Emails from my personal gmail to comcast.net addresses have been blocked for the last 5 days.  I saw the message below in another thread and called CSA.  The tech could not find a block on my email address and suggested I call Google to see what is blocking on their end.  I would be very surprised if Google was blocking but I will give it a try.  Any other ideas?

"I would recommend contacting our Customer Security Assurance Team, as they specialize in assisting with any security email or website issues. They can be contacted by phone at 1-888-565-4329 and are available every day from 8:00 am - 12:00 am EST."