You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Larry Jones here.

ASSISTANT: How may I help you out?

USER: I would like to book a ticket from LAS to OAK, can you please help me with that?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: The travel dates are from 07/04 to 07/06.

ASSISTANT: Sorry, there are no flights found in our database.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for choosing us.