You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Donald Williams. Can you please book me a ticket with the fare of 1000 to meet old best friends?

ASSISTANT: Sure, kindly mention your travel dates?

USER: My travel dates are from 12/26 to 12/28.

ASSISTANT: Can you please provide me your airport codes?

USER: It is round trip from BOS.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for reaching us.