If you want to allow users to cancel a booking they have already submitted, you can enable the “Allow cancellation” option from Booking Options > Settings > Booking Terms in the product edit page.
Your users will be able to cancel their booking no later than xx days/months before the booking start date.
Users can cancel the booking from their “My Account” page on your website.
The admin will see the booking appear with the “Cancelled” status.
Note: The plugin does not handle any other refund option related to booking cancellation.