You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: I need to reserve a ticket from ATL to SFO, can you help me?

ASSISTANT: Sure, May I know the travelling dates?

USER: My trip dates are June 20 to 22.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any other requirements?

USER: Please ensure that my depart time must be in evening.

ASSISTANT: May I know your name?

USER: I am Katherine Thomas.

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

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us.