You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I help you?

USER: I am Jack Williams. I want to meet my family friend, so please help me for booking a flight ticket.

ASSISTANT: Will you please provide the details of your journey?

USER: My source and destinations are CO-DEN, MN-MSP. And my departure day is Dec/1, return day is Dec/3.

ASSISTANT: Just  a minute I will let you know the information.

USER: OK.

ASSISTANT: Sorry, No flights are found on your given information.

USER: OK, thank you for your service.

ASSISTANT: Thank you for reaching us.