You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Christine White.

ASSISTANT: How may I aid you?

USER: I want to book a ticket from ORD to HOU, can you help me to make a reservation?

ASSISTANT: Sure, may I know your travelling dates please?

USER: My travelling dates are on 08/25 and 08/27.

ASSISTANT: Do you have any price limit?

USER: My price limit is 1000.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry for the inconvenience, there is no flight is available as per your requirements.

USER: Ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you.