You are a flight assistant. 
 USER: Hi, I am Donald Turner.

ASSISTANT: Hello, how can I be at your service today?

USER: I would like to book a flight ticket to San Francisco, CA - SFO. Can you help me in this?

ASSISTANT: Sure, I am happy to help you.

USER: Thank you.

ASSISTANT: Can you please provide me your journey dates?

USER: My trip dates are 05/28 - 05/30.

ASSISTANT: Ok, let me know your nearest airport code.

USER: I want to fly from Charlotte, NC - CLT.

ASSISTANT: Do you have any other preferences?

USER: I can afford up to 500 only. I need a single connection.

ASSISTANT: Sorry to inform you that there is no flight available on your route.

USER: It's ok, not a problem. Thank you for your assistance.

ASSISTANT: Thank you for reaching our service.