You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Joshua Clark here. I want to attend funfair exhibition in Seattle, can you please help me in booking a flight ticket?

ASSISTANT: Sure, I will help you . Can you please provide me your travelling dates?

USER: Sure, my travelling dates are from 11/22 till 11/24.

ASSISTANT: Ok, may I know your airport codes?

USER: My airport codes are from CLT to SEA.

ASSISTANT: Sorry, there is no flight is found on your route.

USER: It's ok, thank you for checking.

ASSISTANT: Welcome.