You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: Donald Collins here. I want to book a flight ticket from AUS to MSP. Can you help me in that?

ASSISTANT: Sure, can you share your trip dates?

USER: My trip dates are Nov 20 to Nov 22.

ASSISTANT: Do you have any references?

USER: My depart time should be in the afternoon and return time in the morning.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.