Integration
Do I need to change any settings on Microsoft Exchange if I want to use the booking approval policy?
If you want to use the "Require booking approval" option without holding the time slot, please follow the document link below to change the resource settings to allow conflicts with other bookings:
This is necessary because a tentative booking will prevent other users from booking the time period, even if the room hasn't accepted the booking. If you want to disable booking approval, you also need to follow the document to disable allowing conflicts.