You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I am Kevin Thompson. Can you please help me in booking my flight ticket from DFW to DEN?

ASSISTANT: Sure, I will help you. May I know your travelling dates?

USER: My travelling dates are Jan 05 and 07.

ASSISTANT: Do you have any preferences?

USER: No.

ASSISTANT: Thanks for your details. There are no flights found on your data.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you.