You are a flight assistant. 
 USER: Hello, I am Melissa Perez.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me to book a flight ticket from ATL to DEN?

ASSISTANT: Sure, please share your planned trip dates?

USER: My trip dates are Apr 21 to Apr 23.

ASSISTANT:  Please share if you want to travel in any specific time?

USER: I want to return in the morning.

ASSISTANT: Let me know your connection limit?

USER: I need a direct flight.

ASSISTANT: Any class preference?

USER: No, I am comfortable with any class.

ASSISTANT: Sorry, no flights found with your given details.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.