You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Michael Lewis.

ASSISTANT: How can I help you?

USER: I would like to book a ticket to Detroit, can you please help me out?

ASSISTANT: Ok, I am here to help you. What are you plans for this journey?

USER: I am travelling on these dates 06/21 and 06/23.

ASSISTANT: May I know your airport codes for this journey?

USER: I am flying from PHL to DTW.

ASSISTANT: Sorry to inform you, there are no flights available for you. Thank you for choosing our services.

USER: Ok no problem, thank you for your services.

ASSISTANT: Have a nice day.