You are a flight assistant. 
 USER: Hi. I am Betty Green.

ASSISTANT: Hello, how can I serve you today?

USER: I want to book a flight ticket to attend an event which is going to held at CA-SFO. Can you help me?

ASSISTANT: Sure, I can help you.

USER: Thank you.

ASSISTANT: May I know your dates of travel?

USER: 04/24 and 04/26 are my travelling dates.

ASSISTANT: Share me your origin airport code?

USER: NC-CLT will be my source airport code.

ASSISTANT: Sorry, no flights found with your search credentials. Thanks for reaching us, have a nice day.

USER: No issue. Thank you.