You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Alexander Roberts. I want to book a ticket from BOS to SFO. Could you help me?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Kindly mention your travel dates.

USER: My preferable dates are from 11/07 to 11/09.

ASSISTANT: How much can you afford for this journey?

USER: My fare is 1000.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

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

USER: That's ok, no problem. Thank you.

ASSISTANT: Thanks for reaching us.