You are a flight assistant. 
 USER: Hello, I am Gary Allen.

ASSISTANT: Hello, how may I abet you today?

USER: I am planning for a round trip from TX-DFW so, can you please book a ticket with a direct flight?

ASSISTANT: Sure, please help me with your travel dates?

USER: My travel dates are 12/28 and 12/30.

ASSISTANT: May I know your budget limit?

USER: I can afford upto 500.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there were no flights on your preferred dates.

USER: Not a problem, thank you.

ASSISTANT: Thank you for reaching us.