Handful of email messages not syncing

I have a handful of messages in one of my accounts (haven't checked the other one) that are not syncing using IMAP. They were received and synced a week ago. (Apparently there was a certificate change that happened a week ago also according to posts in here)

I wouldn't have noticed it, except I went to look for one of them and I couldn't find it anywhere on my iPhone or in Outlook365 on my Windows computer. I logged into cox.net and they show in the inbox.

Is anyone else experiencing this? Anyone know of a way to force them to sync? Thanks!