It may take up to 24 hours after activating the setting in the Booking Rules section of your Business Profile before booking options first become available through your Google My Business listing. This time allotment allows Google to add your Business information, Service Menu, and availability to Reserve with Google. Once the connection is complete, availability will update in real time for online booking.
Note: After the connection is complete, changes to your Business Profile (such as editing your Service Menu) may take up to 24 hours to display in Google. Only availability updates in real time.