You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Brian Perez. I would like to travel from SFO to LGA. Can you please help me to book a flight ticket?

ASSISTANT: Sure, I am here to help you. May I know how much you can pay for this ticket?

USER: I can afford upto 5000.

ASSISTANT: Ok, can I know on  which dates you want to travel?

USER: My travelling dates will be on 12/13 to 12/15.

ASSISTANT: Please stand by.

USER: Ok.

ASSISTANT: Thank you for your time, sorry we didn't find any flights with your details.

USER: Ok, not an issue.

ASSISTANT: Thank you for opting us, have a nice day.

USER: Thank you.