Exchange not syncing across devices.
I've been using Exchange with Mac mail with no issues for years. Recently, my Exchange email account stopped updating across devices. Specifically, my Exchange mailbox on my desktop doesn't sync with any of my other devices. I've seen other folks online have solved similar problems by signing out and signing back in to the account, but that hasn't helped me. All of my systems and apps are up to date. Any other advice?
iMac 27″ 5K, macOS 10.15