Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi Erin,
Thank you for posting. As an admin you may run message trace to check why message get delayed.
If you are not admin, please may contact your administrator to find out what happened to an email message by running a message trace in the classic Exchange admin center (EAC). After running the message trace, you can view the results in a list, and then view the details about a specific message (Look for a delivery status of Pending to explain why the message was delayed received). See Run a Message Trace and View Results
Your patience and cooperation will be highly appreciated. Have a nice day and stay safe!
Best regards,
Shyamal