You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I want to attend a Marriage in Houston. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I will help you with that. Can you please provide your preferable dates of travelling?

USER: My travelling dates are Dec 13 and Dec 15.

ASSISTANT: Can you please provide your origin and destination airport codes for booking?

USER: My airport codes are BOS and IAH.

ASSISTANT: Do you have any class preference?

USER: I want to travel in economy class.

ASSISTANT: Any connection limit do you have?

USER: I need single connection.

ASSISTANT: Is there any other preferences do you have?

USER: I want to departure on afternoon and return on morning.

ASSISTANT: May I know your name to book the flight ticket?

USER: Brian Perez here.

ASSISTANT: Unfortunately there are no flights running on your route with your required preferences.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for reaching us, have a great day.