Outlook calendar suddenly stopped syncing with S8 calendar

[Android Central Question]

My work outlook calendar that is accessed from my desktop or from my S8 is synced with the calendar app on my phone (I'm just using the regular calendar app that came with the phone). That same calendar is also synced with my two separate gmail calendars. syncing both ways - where calendar items entered on my phone, sync with my outlook desktop and vice versa. It has been working all this time, and then all of a sudden 1 or 2 days ago, stopped working. All of the sync settings have not changed and are still set to sync. I re-started my phone twice. It's still not working.