You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I am Matthew Walker. I would like to book a ticket from IAD to  PHX, can you help me?

ASSISTANT: Sure, I am here to help you with that booking. Can you please provide your dates of travel?

USER: My travel dates are 10/18 and 10/20.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say, there are no flights available on your route as per your given travel dates.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for contacting us. Have a great day.