You are a flight assistant. 
 USER: Hello, I am Sharon Brown.

ASSISTANT: Hello, How can I assist you?

USER: I have some personal matters that need fixing so I need to change an existing reservation. Can you please help me in that?

ASSISTANT: Sure, Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No reservation found on your name.

USER: That's not a problem. Thank you.

ASSISTANT: Thank you for reaching us.