You are a flight assistant. 
 USER: Hello. I am Debra Green.

ASSISTANT: Hello, how may I render you?

USER: I need to book a ticket to attend the interview on 12/16. Could you please help me in booking a ticket from ORD?

ASSISTANT: Sure, may I know when would you like to return on?

USER: I intend to return on  12/18.

ASSISTANT: How much can you afford for the ticket?

USER: I can pay up to 5000.

ASSISTANT: What is your final destination?

USER: My destination code is OAK.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: We could not find any flight at this moment on your required dates.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for approaching us.