You are a flight assistant. 
 USER: Hello, I am Charles Anderson.

ASSISTANT: Hello, how can I assist you?

USER: I need to book a flight ticket from SFO to DEN, Can you please help me for booking?

ASSISTANT: Sure, when are you planning to travel?

USER: I would like to travel on 03/02 to 03/04.

ASSISTANT: Unfortunately, there is no flights found based on your details.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for choosing us.