You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you today?

USER: On 01/01 I have planned to celebrate new year with my girl friend at Alki Beach Park in Seattle. For that I need to book a flight ticket under a fare of 500, can you serve me in this?

ASSISTANT: Sure. May I know your name?

USER: Sure, Dennis Roberts is my name.

ASSISTANT: Help me with your return date.

USER: On 01/03 I have to catch return flight.

ASSISTANT: In which airport do you want to takeoff and land?

USER: I want to takeoff from Boston, MA - BOS. And I want to land on Seattle, WA - SEA.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.