You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I serve you?

USER: I would like to book a flight ticket with the price limit 500. Can you help me?

ASSISTANT: Deffinitely, may I know your good name please?

USER: I am George Garcia.

ASSISTANT: Ok. Please let me know your airport codes.

USER: My boarding point is DC-IAD and my landing point is PA-PHL.

ASSISTANT: Can you share your journey dates?

USER: I will depart on 02/21 and I intend to return on 02/23.

ASSISTANT: Please wait a while.

USER: Ok.

ASSISTANT: Thanks for your time, there was no flight found on your dates.

USER: Ok, no problem.

ASSISTANT: Thanks for contacting us, have a nice day.

USER: Thank you.