How to Cancel a Lufthansa Business Flex Ticket +1-833-319-4940 or +1-833-319-6372 – To cancel your Business Flex ticket, log in to the My Bookings section on Lufthansa’s official website or open the Lufthansa mobile app. Enter your last name and booking reference, locate your flight, and if eligible, click on the Cancel Booking button. Once the process is completed, you’ll receive a confirmation email automatically.