You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Edward Hill, want to travel from DEN to DCA on 01/04. Will you please help me in booking my ticket?

ASSISTANT: Sure, please provide the dates of journey. Your return date.

USER: My return date is on 01/06.

ASSISTANT: Ok, please give me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no flights available on those dates.

USER: Oh! It's ok, no issue, I will go on some other day.

ASSISTANT: Thank you for reaching us.

USER: My pleasure.