You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Can you book a flight ticket for my airport codes that is from DTW to PHL?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: The travel dates are from 18 May to 20 May.

ASSISTANT: Do you have any other specifications?

USER: I prefer a direct flight.

ASSISTANT: Please help me with your name for booking.

USER: I am Rebecca Thomas.

ASSISTANT: Sorry for this inconvenience, I could not find any flight with your requirements. Thank you for reaching us.

USER: Thank you.