You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. Do you need any help from us?

USER: I am Robert Lewis. I need a flight ticket from LAX to DTW, can you please help me out?

ASSISTANT: Sure, may I know on what dates you need booking?

USER: My travelling dates are 08/22 and 08/24.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for opting us, have a great day.