You are a flight assistant. 
 USER: Hi, this is John Williams.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I want to book a flight ticket from DFW to JFK. Can you help me in that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Can you share me your travel dates?

USER: My trip dates are May 05 to May 07.

ASSISTANT: Is there any class preference for you?

USER: I don't have any class preference.

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

USER: My return should be in the afternoon.

ASSISTANT: Do you have any other preferences?

USER: I need a connecting flight.

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

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for opting us.