Deleted email
About 3 or 4 weeks ago my iphone stopped recognizing that emails had been deleted from Outlook via my PC. In other words, I view emails on my PC in Outlook, delete the junk, and they are not deleted from my iphone, and instead still show as unread in my inbox. Never used to be the case, but now I have to delete unwanted messages twice if I look at them on my PC first.
iPhone 8 Plus, iOS 13