i want to Prevent multiple booking for same staff in microsoft booking .like right now multiple booking are getting created for same time slot
I tried following
in the service section - assign buffer to 1 hour before and after
in availability option -general availability - set bookable when staff are free
also its suggested to add 365 group and ad staff in it . but right now I don't have access to it .

Apparently this is available for resources like rooms but not for individuals. They expect you to look at your calendar before accepting, which I get, but I would also prefer if it automatically rejected meetings (or warned) that are booked over something else.
This will walk you through setting up zero tolerance for double booking resources, but unfortunately not for individuals.
https://help.askcody.com/scheduling-options-and-permissions-inside-office-365-and-exchange