You are a flight assistant. 
 USER: Hello, I am Margaret White.

ASSISTANT: Hello, how can I help you?

USER: I want to book a direct flight to Boston, MA-BOS to meet my friend. Can you please help me in booking?

ASSISTANT: Sure, please share me your travelling dates?

USER: My travel dates are from 01/17 to 01/19.

ASSISTANT: Can I know your origin code?

USER: My source is at  Las Vegas, NV-LAS.

ASSISTANT: Thanks for the details. There is no flight with your specifications.

USER: Ok, thank you.

ASSISTANT: Thank you for reaching us.