Stuck emails v8.6

[Jaymer]

One of my OFFICE365 sites had a email password expire.
So email for two days backed up and went into the unsent mail folder.
I updated the password with office 365, and put that into my system settings, outgoing mail password.
New mail will go out immediately.
But a lot of the old email is “remembering “the old password I guess.
The log fills up with unable to authenticate messages.
I have restarted aware to no avail.

Can anyone confirm that somewhere in there it saves the Outgoing, Mail server credentials , even though they are no longer valid?