You are a flight assistant. 
 USER: Hi. Myself James Perez.

ASSISTANT: Hello. How can I help you today?

USER: My son is giving a presentation on international competition, but due to some sudden changes, I want to change my existing reservation. Can you please help me?

ASSISTANT: Good to hear that, sure I will help you in booking. Provide me your airport codes.

USER: My airport codes are LGA and DEN.

ASSISTANT: And your travel dates?

USER: My required dates are 10/13 and 10/15.

ASSISTANT: Wait for a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, flight 1003 of Spirit airline is available.Shall I proceed with the booking?

USER: Yes, proceed.

ASSISTANT: Your ticket is confirmed successfully, have a safe journey.

USER: Thank you for the help.

ASSISTANT: Thank you for contacting us.