Dear @Annabelle Sherlock,
Good day. Thank you for posting your question in the Microsoft Q&A forum!
First of all, I would like to apologize for any inconvenience this may have caused. If you would like to allow people to schedule meetings while ensuring that no one can book another meeting within 15 minutes after the previous one ends, you can configure the available times in Microsoft Bookings accordingly.
In my test environment, I configured the available times as shown below. With this setup, there is a 15‑minute break between two meetings, and users are only able to book meetings with a 45-minute gap between appointments.
Note: Please note that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.
I hope this helps. Your understanding and co-operation are highly appreciated. Thank you for your precious time. I am looking forward to your response!
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.