You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Myself Sharon Williams, owing for the client meeting, I want to change my reservation. Can you help me?

ASSISTANT: Please give me a minute.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for reaching us. Have a great day.