You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I provide assistance to you?

USER: I am Anna Mitchell, I want to book a direct flight to meet my friend on his birthday. Can you book a flight under fare is 500?

ASSISTANT: Sure, can I know your depart and return dates?

USER: I will fly on 07/15 and return on 07/17.

ASSISTANT: Where do you want to board at?

USER: My source point is AZ-PHX and destination is CA-SFO.

ASSISTANT: Where do you want to land at?

USER: I will land on CA-SFO.

ASSISTANT: Okay, let me check the availability of flights.

USER: Sure.

ASSISTANT: Sorry, we could not find any direct flight as on your request.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for opting us.