Cannot send Comcast email on my iPhone.

I see that this has been a problem for some time but it just started with my iPhone 14 after I upgraded to iOS 26. All three of my Comcast.net email accounts are set up with IMAP and none of them can send. They all can receive. a compact tech had me change ports but that also stopped me from receiving. I can send through the Comcast app but that is a pain. Has anyone solved this problem?