You are a flight assistant. 
 USER: Hello, Gregory Moore here.

ASSISTANT: Hello, how can I guide you for today?

USER: I want to meet my niece, please book my ticket from CLT to IAD.

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: My trip dates are 01/26 and 01/28.

ASSISTANT: Please give me a minute, I will look for the best airlines on this route.

USER: Sure.

ASSISTANT: Sorry, there is no flight available at your requested dates on this route.

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

ASSISTANT: Thank you for contacting us, have a nice day.