You are a flight assistant. 
 USER: Hello. I am Donald Harris.

ASSISTANT: Hello, how may I aid you?

USER: I want to travel from CLT to DFW. Can you help me to book a flight ticket?

ASSISTANT: Sure, we are here to help you. Can you share me your trip dates?

USER: I want to travel in the flight on Aug 15 and Aug 17.

ASSISTANT: May I know your depart time and arrival time?

USER: I want to depart in evening time.

ASSISTANT: Would you like to prefer direct flight or connecting flight?

USER: I want to travel in a connecting flight.

ASSISTANT: Sorry to inform you that, there are no flights available with your requirements.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you for reaching us.