You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to book a ticket on 12/06 to meet my client, can you help me to book a return ticket on 12/08?

ASSISTANT: Ok, please help me with your source and destination codes.

USER: I will fly from CA-LAX and land on airport CO-DEN.

ASSISTANT: May I know your name, please?

USER: My name is Christine Thompson.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, there are no flights available currently.

USER: Thank you for the information.

ASSISTANT: Thank you for approaching to us.