This looks like a Microsoft issue with the old user interface. If you switch to the "New Outlook", the search is working for me.
Maybe this is Microsofts way of pushing the new UI :-D
flexier
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Last seen
User for
Post
Replies
Boosts
Views
Activity
Similar problem here. Since Big Sur my USB-C ports randomly stop working in respect to charging. The battery runs empty although the Macbook is connected to the charger. If I change the port it suddenly charges again. This is particularly annoying when leaving the Macbook closed lid and coming back after some time finding the Macbook battery completely drained.