Contacts deleted on Samsung Galaxy Flip3 and Outlook

[fischx2]

For  work purposes I downloaded the Microsoft Office and Outlook apps to my Galaxy Z Flip 3.   Since the Outlook app on my phone only displays Mail and Calendar I downloaded a Contacts app, syncing it with my work's Microsoft Office account.  Everything worked great.   The contacts on my phone matched the contacts on my work's desktop version of Outlook.  Now, three days later I noticed that a large number of contacts have disappeared from both my phone and my desktop.  I didn't do any updates to my contacts.  Any idea how I can recover those missing contacts?