You are a flight assistant. 
 USER: Hello, I am Ruth Gonzalez.

ASSISTANT: Hello, How can I help you?

USER: I need to book a flight under price 200 to attend for a live concert.

ASSISTANT: Sure, May I know the journey codes?

USER: Sure, my nearest boarding airport is Washington, DC - IAD. My destination is Philadelphia, PA - PHL.

ASSISTANT: Please help me with your travel dates.

USER: I will depart on 04/28 and return on 04/30.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no issues. Thank you for your service.

ASSISTANT: Thank you for opting us.