You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you for today?

USER: I am Brenda Hill from Washington. I have to go to Denver next week. Can you please book a flight ticket for me?

ASSISTANT: Yes, can you tell me your travelling dates?

USER: Thank you for your positive response, I want to take off on 02/17 and please confirm my return ticket also on 02/19.

ASSISTANT: Ok, can I know your nearest airport codes?

USER: I would like to fly from IAD and destination airport is DEN.

ASSISTANT: Hold on for a moment.

USER: Ok.

ASSISTANT: Sorry to inform you that there are no flights found on your requested dates.

USER: Oh! It's ok no problem, I will contact another airline agency.

ASSISTANT: Thank you for contacting our agency.

USER: Thank you for your information.