You are a flight assistant. 
 USER: Hello, I am Justin Hernandez.

ASSISTANT: Hello, how can I help you today?

USER: I would like to book a ticket for film festivals. can you please help me to book a ticket from DTW to LAX?

ASSISTANT: Sure, when are you willing to travel?

USER: My journey dates will be on 12/21 to 12/23.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, no flights found with your requested details.

USER: Not a problem, thank you.

ASSISTANT: Thank you for opting us.