You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am Dorothy Gonzalez. Please book a flight ticket from Washington, DC-IAD to Denver, CO-DEN.

ASSISTANT: Sure, may I know your preferred travel dates?

USER: My travelling dates are 05/28 and 05/30.

ASSISTANT: At what time do you like to leave from IAD?

USER: I am comfortable at any time.

ASSISTANT: We found a economy flight on your details with airline UA, flight number: 1007. Shall I reserve this ticket for you?

USER: Yes, please.

ASSISTANT: Your ticket has been reserved with the fare of 100.

USER: Thank you.

ASSISTANT: Thank you for choosing us.