You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: Can you book a flight ticket from HOU to DCA to attend my sister's marriage?

ASSISTANT: Sure, when are you planning to travel?

USER: I will start on Nov, 8 and return on Nov, 10.

ASSISTANT: May I know your name please?

USER: Donald Clark here.

ASSISTANT: Do you have any preferences?

USER: I need connecting flight.

ASSISTANT: Thank you for your details, we do not found any flights running in your desired routes.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for reaching us. Have a nice day.