You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. By which way, can I provide assistance to you?

USER: Janet Davis here.

ASSISTANT: Ok.

USER: I am planning to watch a live show of my favourite singer at Washington. Can you please help me in booking my flight ticket from Denver CO-DEN to DC-DCA ?

ASSISTANT: Sure, I am euphoric to help you with booking.

USER: Thank you.

ASSISTANT: When will be you reach Washington and return to Denver?

USER: The event is going to be held on 04/14, So I want to start on 04/13, my return date will be 04/15.

ASSISTANT: Thanks for providing the details, please wait.

USER: Sure.

ASSISTANT: Thanks for your time, Unfortunately there are no flights found on your preferred travel dates.

USER: Not an issue, I will find other alternative. Thank you for your effort in searching a flight for me.

ASSISTANT: Thank you for approaching us, visit again!.