You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I'm Barbara Collins. I am planning to attend music concert at San Francisco, can you please help me with booking a flight ticket?

ASSISTANT: Sure, I will help you. Could you please help me with travel airport codes to search the flights?

USER: My source airport code is LAX and the destination airport code is SFO.

ASSISTANT: Ok, when you are willing  to travel?

USER: Sure, I would like to take off on 04/03 and return back on 04/05.

ASSISTANT: Ok, do you need any other requirements?

USER: Yes, make sure that the connection limit is 1.

ASSISTANT: Ok, please hold on for a minute while I am checking the availability.

USER: Ok, but make sure that the price limit does not exceed 500.

ASSISTANT: Sorry for the inconvenience, there are no flights found in this route.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: You are welcome. Thank you for reaching us.

USER: You are welcome.