You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I will help you with that, please hold on for a moment to check your reservation status.

USER: Ok.

ASSISTANT: May I know your name please?

USER: My reservation was reserved in the name Joseph Phillips.

ASSISTANT: Joseph, I did not find any reservation with your name in my database.

USER: Thank you for searching.

ASSISTANT: It's my pleasure.