You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to visit The Golden Gate Bridge in SFO, can you please help me to book a flight from IAH?

ASSISTANT: Sure, may I know your travelling dates?

USER: I will start on Oct 18th and will return back on Oct 20th.

ASSISTANT: Do you have any depart and return time?

USER: I want to takeoff from IAH in the afternoon.

ASSISTANT: Do you have any class preference?

USER: I am looking for a economy class seat.

ASSISTANT: Wait a minute.

USER: Sure.

ASSISTANT: There are no flights available on your travelling dates.

USER: No problem, thank you for the information.

ASSISTANT: May I know your name for documentation purpose?

USER: Sure, Patrick Hall here.

ASSISTANT: Thank you for reaching us.

USER: You welcome.