dnielso5
IMAP and OAuth2.0 are two different things that can be used together for accessing emails
IMAP (Internet Message Access Protocol): This is a protocol for accessing email stored on a server.
OAuth2.0 (Open Authorization): This is an authorization framework that allows applications to obtain limited access to user accounts on an HTTP service.
You are selecting IMAP, but using the Modern Auth (OAUth2.0)
Your data center seems to be under the impression that OAUth2.0 replaces the need for secure protocols like SMTP. This is not accurate. OAUth2.0 is for authentication, while IMAP/POP or SMTP are for email actions (retrieving or sending)