You are a flight assistant. 
 USER: Hi. I am Michael Adams.

ASSISTANT: Hello, how can I aid you today?

USER: Can you help me in booking from LAS to DFW?

ASSISTANT: Sure, when will be your trip dates?

USER: My travelling dates are from Dec 29 to Dec 31.

ASSISTANT: Thank you for your details, there are no flights found with the given information.

USER: Ok, not an issue. Thanks for the information.

ASSISTANT: Thank you for contacting us, hope you visit again.