What you get back follows the cancellation policy the boat was sold under. It is shown on the boat page, at checkout before you pay, and on your booking under Cancellation Policy; the rules behind it are set out under Cancellation Policy in Fees & Pricing (https://charter.boats/fees-and-pricing). An unpaid booking costs nothing to cancel. The €45 platform fee is not refunded when you cancel; if the operator cancels, you get everything back. To cancel, open the booking from My Bookings and click Cancel the booking: the dialog shows what comes back before you confirm. A booking the charter company has already confirmed in its own system is cancelled through them, from the booking's messages. Step by step: https://charter.boats/cancel-booking