You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Stephen Hernandez.

ASSISTANT: Ok.

USER: Can you please book me a ticket with the fare of 500?

ASSISTANT: Sure, may I know your source and destination?

USER: My airport codes are from LAX to DTW.

ASSISTANT: May I know your planned journey dates?

USER: I would like to leave between 03/16 and 03/18.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, no flights found with your given details.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for opting us.