Apple mail email not syncing on iPhone

Not helpful. Both devices are ALWAYS connected to the internet, yet when I delete e-mails using my iPhone, they remain as "unread" on my Mac24.

These don't sync between devices Contacts, Calendars, Bookmarks, Notes, Voice Memos, shared photos, iCloud Photos, and emails. Each device syncs to the email account server which may be Google, iCloud, AOL, Exchange, Outlook, Yahoo, or any Other. Please see the pic below

If one of the devices is not connected to the internet then it may seem to you that they are not syncing.

Me, too.

Same problem. Phone and computers don't sync with Mac Mail.