You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me in booking my flight ticket from IAH to PHL?

ASSISTANT: Sure, on which dates you would like to have your journey?

USER: My journey dates are 12/25 and 12/27.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Ok, may I know your price limit to proceed further?

USER: Ok, please search with 200 price.

ASSISTANT: Sorry to say, no flights were available with your requirements.

USER: Ok, fine thank you for your help.

ASSISTANT: Thank you for choosing us, have a nice day.