Using New Outlook on Windows for personal email, calendar, and contact management
Hi,
I’m Dyari. Thanks for reaching out.
Are you using the new Outlook for Windows?
Was the Gmail account added using “Sign in with Google”?
Do changes made in Gmail sync back to Outlook?
Also, check Gmail’s Trash and All Mail folders, because Outlook may be archiving messages instead of deleting them.
If the problem continues, make sure all messages are available at Gmail.com, then remove and re-add the Gmail account in Outlook through Settings > Accounts > Email accounts.