To set your cancellation policy:
Go to Menu >> Payments
Click on Cancellation policy
Type your cancellation policy in the Default cancellation policy section
Click Save
Note - You can only enforce a cancellation policy if you collect payment in advance of a booking. If a booking is cancelled, you can choose if you wish to enforce the policy. You are responsible for refunding your customer if they cancel outside of your cancellation window, or if you do not wish to enforce your cancellation policy.