You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I need to change my current reservation due to urgent meeting, can you help me?

ASSISTANT: Sure, can I know your name?

USER: I am John Thomas.

ASSISTANT: Please hold on a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on given name.

USER: That's ok. Thank you.

ASSISTANT: Thank you for reaching us.