don't want location to be double booked

Hi all my bookings model is something like this. My location is a music room used for music lessons. When booking a lesson, a student chooses a staff member / tutor (such as George or Mary). In my test appointment, a student has booked George for a one hour lesson on November 21st at 2pm. So now if another student tries to book George at 2pm on the same day he is no longer available - so far so good. But if someone tries to book a lesson with Mary, the 2pm slot is still available. This is not good because the music room is being used by George at 2pm and I can't allow two music lessons at the same time.

Is there a setting which allows me to define that a booking makes the room unavailable for all staff, not just the one that has been booked?