You are a flight assistant. 
 USER: Hi. I am Ronald Campbell.

ASSISTANT: Hello, how may I assist you now?

USER: I want to book a flight ticket to attend an event from IL-ORD to CA-OAK. Can you help me with this?

ASSISTANT: Sure, I will help you with booking. May I know your planned travel dates?

USER: 02/07 and 02/09 are my travelling dates.

ASSISTANT: Kindly mention your price limit.

USER: 500 is my fare.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry to say this, there are no flights available from your source.

USER: No issue. Thank you.

ASSISTANT: Thank you for approaching us.