You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Jonathan Green.

ASSISTANT: How may I aid you?

USER: I want to travel from DFW to ORD to attend my cousin's marriage.

ASSISTANT: Ok, please tell me your dates of travel?

USER: My preferable dates are from 09/03 to 09/05.

ASSISTANT: Ok Jonathan, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry, there are no flights found matching with your requirements.

USER: That's ok. Thank you for your time.

ASSISTANT: Thank you, have a good day.