You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Could you please book me a flight ticket from IAH to DFW?

ASSISTANT: Sure, I can help you with that. May I know your travel dates please?

USER: I will leave on Apr 28th and return on Apr 30th.

ASSISTANT: Do you need break in between your journey?

USER: Yes, I need 1 lay by.

ASSISTANT: Please let me know if you have any other specifications.

USER: My depart time must be in the afternoon.

ASSISTANT: Can I know your good name please?

USER: I am Catherine Scott.

ASSISTANT: Sorry, no flights available on those dates.

USER: That's fine, thanks for your assistance.

ASSISTANT: Thank you for choosing us.