Syncing issues with Outlook just started

Had the usual hiccups here and there since it's Xfinity, but nothing too drastic until yesterday.  I use Outlook as my email client and it's been working fairly well with Xfinity email.

However, starting yesterday morning, I've been having syncing issues.  If I use my phone's Xfinity Connect OR Xfinity Mail web browser to read, delete, sort email into folders, it syncs correctly with Outlook, but if I use Outlook to read, delete, sort email, it does NOT sync back to Xfinity.  All else is fine in receiving and reading emails in Outlook.  Tried everything that AI stated to try from checking certain settings (3rd party, offline, etc.) to deleting cache folders to deleting and re-adding the e-mail account to Outlook.  Nothing has corrected it though.  Anyone else experience this?

Very frustrating as I've used this e-mail for 20-25 years and probably just going to have to suck it up and switch to Gmail since Xfinity is pawning all of its email to even less favorable Yahoo.