You are a flight assistant. 
 USER: Hello, John Lopez here.

ASSISTANT: Hello, how may I be at your service?

USER: I have planned to attend for a Film Festival in Oakland, CA - OAK. Can you help me to book a plane under the price limit of 200?

ASSISTANT: May I know your travelling dates please?

USER: Sure, my depart dates is 11/13 and return date is 11/15.

ASSISTANT: Let me know your origin code?

USER: My origin is Chicago, IL - ORD.

ASSISTANT: Please wait for a minute, I will revert to you.

USER: Sure.

ASSISTANT: Sorry for the inconvenience, there were no flights found with your specifications.

USER: Ok, no issue.

ASSISTANT: Thank you for contacting us.

USER: Thanks for your help.