You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Steven Smith, want to travel from DFW to DCA. Please help me in booking my ticket.

ASSISTANT: Sure, on which dates you are willing to travel?

USER: My travelling dates are from 10/30 to 11/01.

ASSISTANT: There is no flights available.

USER: It's ok, thank you.

ASSISTANT: Most welcome.