Mail (outlook.com account) on Mobile not synching, showing messsages deleted on SP3

[Lightning_Racer]

On my Lumia 650, the Mail app continues to show email messages deleted from my Outlook.com account on my Surface Pro 3, so it is not synching correctly. It will show the new messages, but the old messages don't go away. I don't want to go through and delete things again, since I might make a mistake, and it sometimes synchs up later. This is annoying because my phone shows XX unread emails, but I'm caught up.

I've checked all the synch settings on the Mail app on the phone. Anyone else have this problem? I don't know if it's just outlook.com, since that's my only email account.