You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Melissa King.

ASSISTANT: How can I help you today?

USER: I am planning to visit Denver to attend a cancer awareness program, can you please book me a ticket from LAS to DEN?

ASSISTANT: Sure, I am here to help you in booking. Can I have your travel dates please?

USER: I am planning to depart on 03/30 and would like to return on 04/01.

ASSISTANT: Please wait a moment.

USER: Sure, I will wait for your response.

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

USER: Ok, not an issue. I will find any alternate for this trip. Thank you for providing information.

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