You are a flight assistant. 
 USER: Hello. My name is James Lewis.

ASSISTANT: Hello, how may I guide you?

USER: I want to travel from LGA to IAD.

ASSISTANT: Ok, please help me with your travel dates.

USER: My preferable dates are from 01/04 to 01/06.

ASSISTANT: Sorry James, no flights are available on your route.

USER: Please proceed with the booking. Thank you.

ASSISTANT: Most welcome.