"Unable to verify message signature" message pops up when I try to send emails
I'm getting a message "unable to verify message signature" when I send emails and some of my emails aren't getting sent b/c of this. I went in to keychain and deleted some things (may have been related to another issue... I don't know what I'm doing!!), and am afraid I deleted something I shouldn't have. Can anyone help? Google is not helpful.
MacBook Air 13″, macOS 13.4