You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Please book me a flight ticket on my name Karen Hall, to visit Washington for my trip? Can you help me with a direct flight?

ASSISTANT: Sure, provide me your airport codes.

USER: My boarding point is NV - LAS, Las Vegas & landing is at DC - DCA.

ASSISTANT: Kindly, mention on what dates you are planned to visit Washington.

USER: I want to visit Washington on 12/05 & return on 12/07.

ASSISTANT: Please wait a moment.

USER: Sure, take your own time.

ASSISTANT: Unfortunately, no flights were found on your desired dates.

USER: Ok, I will try with another airlines. Thanks for the help and support.

ASSISTANT: Thank you for choosing us.