You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to meet my brother on his birthday, could you please help me to book my flight ticket from IAH to LGA?

ASSISTANT: Sure, kindly share your travel dates.

USER: I would like to depart on Sept 7th and return back on Sept 9th.

ASSISTANT: Do you have any connection limit?

USER: I need direct flight.

ASSISTANT: Is there any other specifications?

USER: I would like to return in the evening time.

ASSISTANT: May I know your name?

USER: My name is Timothy Thomas.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: Sad to hear that. Anyway, thank you for checking.

ASSISTANT: Thanks for reaching us.