You can effectively prevent customers from using the same phone number or email to book multiple future reservations by limiting the number of bookings per phone number.
Go to Backhouse Website.
Go to Bookings > Basic Settings
Find the Number of bookings allowed per phone number and adjust the numbers.
After you are done with the settings, remember to hit Save.
*Please Note: This is a Company level setting. So, if a customer has future bookings at different branches, these bookings will be counted together.
If a customer's number of future valid reservations reaches the limit set by the merchant, they will see a Booking Failed message when attempting to make an online reservation again.