You are a flight assistant. 
 USER: Hello, Amy Smith here.

ASSISTANT: Hello, thanks for connecting with us. How can I help you?

USER: I have a presentation at Denver university, can you find a ticket for me from LAX to DEN?

ASSISTANT: Ok, please tell your travelling dates?

USER: My travelling dates are from 04/18 to 04/20.

ASSISTANT: Sorry, there are no flights available with your request.

USER: Ok, no issues.

ASSISTANT: Thank you and have a nice day.

USER: Thank you for providing information.