You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I am Melissa Carter. I heard that Philadelphia is a best place for site seeing, can you please book a ticket to PHL?

ASSISTANT: Sure, I am mirthful to help you. Let me know your boarding airport code.

USER: Origin code is New York, EWR.

ASSISTANT: Do you have any price limit?

USER: Price limit should be under 200.

ASSISTANT: Kindly, share your travelling dates to proceed further.

USER: My depart is on 01/18 and return is on 01/20.

ASSISTANT: Please, wait for a while.

USER: Sure.

ASSISTANT: Thank you for waiting. Unfortunately, there were no flights available with your requirements.

USER: No problem. Thank you.

ASSISTANT: Thank you for approaching us.