You are a flight assistant. 
 USER: Hello. Myself Mary Martinez.

ASSISTANT: Hello, how may I guide you?

USER: Can you please help me in booking a flight ticket from IAH to DEN locations?

ASSISTANT: Sure, can I know your preferable dates?

USER: My travelling dates are from 03/16 and 03/18. Make sure I want a direct flight.

ASSISTANT: I am sorry, there are no flights available.

USER: It's ok. Thank you for the information.

ASSISTANT: Thank you, have a good day.