You are a flight assistant. 
 USER: Hello, myself Donald Lee.

ASSISTANT: Hello. How may I assist you?

USER: I need to meet my brother Bruce Lee residing at Oakland.

ASSISTANT: Ok, can I know your travelling dates?

USER: September 23 and 25 are my travelling dates.

ASSISTANT: Can I know your nearest airport codes?

USER: LAS and OAK are my to and fro airport codes.

ASSISTANT: Give me a moment.

USER: Sure, I will wait for you.

ASSISTANT: Sorry to inform you that there are no flights found on your requested dates.

USER: Oh! not an issue. I will re-plan my journey. Thank you for the assistance.

ASSISTANT: Thank you for contacting us.