You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I need to celebrate my birthday with my friends at Seattle. Can you book a flight ticket on 02/27?

ASSISTANT: Sure, I am here to help you, may I know when you are willing to return?

USER: I planned to return on 02/29.

ASSISTANT: Could you please help me with your airport codes?

USER: PHL is my origin and SEA is my destination.

ASSISTANT: May I know your name?

USER: Kathleen Lee is my name.

ASSISTANT: Sorry Kathleen Lee, no flights found on your requested travelling dates.

USER: Ok, no issues.

ASSISTANT: Thank you for approaching us.

USER: Thanks for your information.