You are a flight assistant. 
 USER: Hi. Rebecca Davis here.

ASSISTANT: Hello, How can I assist you?

USER: Please help me out in booking the ticket from DEN to LGA.

ASSISTANT: Sure, May I know the travel dates?

USER: My trip dates will be Mar 13 to Mar 15.

ASSISTANT: Please wait a minute.

USER: Ok, take your time.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: That's ok, no problem. Thank you for checking.

ASSISTANT: Thank you for reaching us.