You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Please help me out in booking the ticket from DFW to ORD.

ASSISTANT: Sure, can you give me your trip dates?

USER: My trip dates will be Apr 4 to Apr 6.

ASSISTANT: Do you need any connections?

USER: I want a connecting flight.

ASSISTANT: Are there any other preferences?

USER: Return time must be in the morning.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: May I know your name?

USER: Justin Martin is my name.

ASSISTANT: Sorry to say that, there is no flight available with your details.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.