You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Patrick Smith. Can you please help me in booking my flight ticket from DEN to LGA?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: My travelling dates are 05/31 and 06/02.

ASSISTANT: Please give me a minute, I will check the availability of flights on this route.

USER: Ok, sure.

ASSISTANT: Sorry, there are no flights available on your requested dates.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for contacting us, have a nice day.