Multi-turn user requests:
user: I have to arrange a flight from San Francisco to Los Angeles for my journey next month November on two days after close of the 14th day in the year 2024. I'll be flying business class, and I'll be settling the payment using my American Express card with id 'AMEX123456789'. Would you be able to take care of this reservation using access token 'abc123xyz' for me?
user: Regrettably, unexpected situations have come up, and I've had to alter my plans. Would you kindly cancel the flight booking that I made previously?

Ground-truth function call sequence:
TravelAPI.get_flight_cost
TravelAPI.book_flight
TravelAPI.cancel_booking