You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I am Katherine Scott. I am planning to attend my friend marriage in Denver, can you please help me to book a flight ticket from PHL to DEN?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: Sure, my travelling dates are from 03/27 to 03/29.

ASSISTANT: Please wait for a moment.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry to say, no flight is available for you.

USER: It's ok, no more issues.

ASSISTANT: Thank you for reaching us.

USER: Thank you for checking.