You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Benjamin Hill.

ASSISTANT: How can I help you today?

USER: I need to travel AUS and MSP, can you please reserve flight ticket?

ASSISTANT: Sure, I am here to help you in booking process. Can you please share your travel dates?

USER: My travelling dates are Apr,19 and Apr,21.

ASSISTANT: Do you have any airline preference?

USER: No, I don't have any preference.

ASSISTANT: Do you have any specification?

USER: My depart time should be in the evening.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available on your particular travel dates.

USER: That's ok, thank  you for searching the flights.

ASSISTANT: Thank you for reaching us, have a nice day.