You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you out?

USER: Cynthia Thomas here. I want to travel from ATL to LAS, can you please help me to book my flight ticket?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: Sure, I would like to depart on Dec 3rd and I want to return on Dec 5th.

ASSISTANT: Sorry, there are no flights found.

USER: Oh! Sad to hear that. Anyway, thank you.

ASSISTANT: Thank you for reaching us.