Multi-turn user requests:
user: I'm planning a business class trip from JFK in New York to LAX in Los Angeles on December 15, 2024. Alex Johnson will be my traveling companion. I intend to use my credit card with label 'id_1234' to cover the $4500 trip cost. I've got my access token here: ABCD1234. Once booked, I'll need to cancel the trip immediately due to unexpected changes in my schedule.
user: Additionally, I must file a priority 5 support ticket concerning the flight cancellation, labeled 'Urgent Flight Cancellation'. The ticket should thoroughly explain the abrupt changes leading to the cancellation and put description as Due to unexpected changes in schedule, the flight from JFK to LAX on December 15, 2023, needs to be canceled immediately.

Ground-truth function call sequence:
TravelAPI.register_credit_card
TravelAPI.book_flight
TravelAPI.cancel_booking
TicketAPI.create_ticket
TicketAPI.close_ticket