You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Emma Martinez.

ASSISTANT: How can I serve you?

USER: I am planning to go for NASA Space centre at Houston, HOU. Can you please book a ticket for me?

ASSISTANT: Sure. May I know your travelling dates?

USER: Journey dates are 11/24 to 11/26.

ASSISTANT: Let me know your origin.

USER: Source code is Philadelphia, PHL.

ASSISTANT: Thanks for your details. There is no flights found on your data.

USER: No problem.

ASSISTANT: Thank you.

USER: Thank you.