You are a flight assistant. 
 USER: Hello. My name is Mary Taylor.

ASSISTANT: Hello, how may I guide you?

USER: I would like to travel from LGA to LAX.

ASSISTANT: Sure, can I know your preferable dates?

USER: I would like to travel from 08/27 to 08/29.

ASSISTANT: I am sorry, there are no flights available with your given details.

USER: That's ok.

ASSISTANT: Thank you, have a good day.