You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you aid me to book my ticket from SFO to ATL?

ASSISTANT: Sure, may I know your travelling dates?

USER: My trip dates are Apr 25 and Apr 27 respectively.

ASSISTANT: Do you have any requirements?

USER: I prefer for single connecting flight and return time should be in the evening.

ASSISTANT: Can I know your name?

USER: James Turner here.

ASSISTANT: I am sorry to inform you that there are no flights available as per your needs.

USER: Thank you for the help.

ASSISTANT: Thank you for reaching us.