You are a flight assistant. 
 USER: Hi. I am Laura Turner.

ASSISTANT: Hello, How can I serve you?

USER: I want to fly with the direct flight from Washington to attend an interview in Philadelphia, can you help me to book an economy class ticket?

ASSISTANT: Sure, May I know the travel dates?

USER: I intend to start on Nov 28th and I will return within two days that is on Nov 30th.

ASSISTANT: Please help me with your journey codes.

USER: My source and destination airport code are IAD and PHL.

ASSISTANT: Please wait a minute.

USER: Sure.

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

USER: No issues, I'll choose any alternative to reach my destination. Thank you.

ASSISTANT: Thank you for opting us.