You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Brenda Evans. I want to go for a flower festival at San Francisco. Can you please book a ticket with a price limit of 500?

ASSISTANT: Ok, I will search your flight ticket with in your limit. Can you please send me your trip codes?

USER: I need to start my journey at PHL and return from SFO.

ASSISTANT: Please provide me your travel dates?

USER: My scheduled dates are 07/10 and 07/12.

ASSISTANT: Do you want any halt in between your journey?

USER: I need a halt.

ASSISTANT: Sorry Evans, I did not find any flight ticket in your route.

USER: Ok, no issue. Thanks for your information.

ASSISTANT: Most welcome.