Email stopped working

I received email as usual on Aug. 30. Since then I have received just 2 emails, on different days. 

I have checked this on the comcast.net web email app, and on the Xfinity Android app (and in Outlook and the Gmail app).

Right before I stopped receiving email, my email box was full and I had to delete emails, according to messages from the server. So I did that, and I no longer receive messages saying the inbox is full nearly full. But my email never resumed functioning normally. 

I may well have messed up a setting, but I can't see anything wrong. I have looked through the settings but did find anything that looked wrong to me. 

What should I do?