You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Richard Martinez. My family tour trip got postponed, so I want to change an existing reservation. So please help me in changing the reservation.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: I found your reservation. Please share your travel dates.

USER: I want to fly on 05/09 and return on 05/11.

ASSISTANT: May I know your airport codes?

USER: My airport codes are MN - MSP, CA - SFO.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Flight 1027 of Delta airlines is available for you with 1 connection. Shall I book?

USER: You can proceed to booking.

ASSISTANT: Your ticket is booked successfully.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.