You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Larry Garcia. I am planning to book a ticket from MSP to HOU. Can you please help me out to book a flight ticket?

ASSISTANT: Sure, help me with your trip dates.

USER: I am planning to travel on 07/21 and return back on 07/23.

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

USER: That's fine. Thank you for your help.

ASSISTANT: Thank you for reaching us.