About two weeks ago, my IMAP account on Mail on OS X Catalina started having issues it never had before; long after moving to Catalina. If I read a message it doesn't get noted as Read. I can manually mark it as Read but it instantly gets remarked as Unread. I can Delete a message over and over, but it just keeps on coming back. A day or so later, it all works on those same messages but new messages take on the issues.
Three other IMAP accounts through other services are working just fine. It's only my GoDaddy account doing it. I've run utilities and deleted the account from the computer but the reestablished account took on the same issues, so it remains limited to GoDaddy.
If I disconnect from the internet, I can successfully mark the messages are Read or Delete them. As soon as I reconnect to the internet, the same messages get marked again as Unread and others that were Deleted come back. So it's clearly an issue of the communication between Mail and GoDaddy's servers.
How can I resolve this?
Today I received a bunch of messages from January 2018 in my email client.
I checked my GoDaddy Webmail and sure enough, there are a bunch of messages from January 2018 that are back and marked as Unread.