You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am planning to visit Detroit to meet my friend, can you please book me a ticket from SEA to DTW?

ASSISTANT: Sure, can I know the travel dates please?

USER: My preferable journey dates are from 07/20 to 07/22.

ASSISTANT: May I know your name please?

USER: My name is Lisa Young.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: Sorry Lisa, there are no flights on your dates.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for approaching.