Hi Daniel,
You may first log onto the webmail interface of your Exchange account and then check whether your emails and folders are really lost. If the emails and folders are indeed lost, I'm afraid you may have lost them if you don't have any backup copy.
You may contact your Exchange admin and see whether they have a backup copy of your mailbox.
If you have a backup copy with Mac time machine, you can also restore your emails and folders from it.
Regards,
Steve Fan
Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact
tnsf@microsoft.com.

Click
here to learn more. Visit the dedicated
forum to share, explore and talk to experts about Microsoft Teams.