You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am Dorothy Thompson. I am planning to book a ticket from BOS. Can you please help me out?

ASSISTANT: Sure, can you please share your travel dates?

USER: I am planning to travel on 11/19 and return back on 11/21.

ASSISTANT: Could you please help me with the destination airport code?

USER: My destination code is EWR.

ASSISTANT: Let me check for the availability of flight.

USER: That's fine.

ASSISTANT: Dorothy, I am sorry to inform you that there is no flight available at your requested dates.

USER: That,s fine, thank you for your help.

ASSISTANT: Thank you for contacting us.