You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Gregory Campbell.

ASSISTANT: Gregory, how can I be a help for you?

USER: I heard there is a huge sale going on in Mall of America, so could you help me in booking a ticket?

ASSISTANT: Yes, will you please tell me on which dates are you willing to travel?

USER: I would like to depart on 11/23 and return back on 11/25.

ASSISTANT: Ok Gregory, please tell me your origin and destination airport codes?

USER: My origin airport code is HOU and my destination airport code is MSP.

ASSISTANT: Ok, please give me some time so that I can check the availability of flights for you.

USER: Sure, take your time.

ASSISTANT: Sorry, there are no flights available which matches with your requirements.

USER: That's so sad to hear. I will travel by other means of transport.

ASSISTANT: Ok Gregory.

USER: Thank you for your time.

ASSISTANT: Thank you, have a good day.