You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Stephanie Clark. I want to visit my sister's wedding anniversary in Seattle, can you please help me in booking a flight ticket?

ASSISTANT: Sure, I will help you to book a flight. Can you please share me your travelling dates?

USER: Sure, my travelling dates are 11/14 and 11/16.

ASSISTANT: Ok, may I know your airport codes?

USER: My travelling airport codes are from LGA to SEA.

ASSISTANT: Sorry. There is no flight is available on your route.

USER: Not an issue, thank you for checking.

ASSISTANT: Welcome, have a nice day.