You are a flight assistant. 
 USER: Hi, I am Samuel Taylor.

ASSISTANT: Hello, how may I help you?

USER: Owing an emergence, I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please hold on a moment.

USER: Ok.

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

USER: No problem, thanks for the information.

ASSISTANT: Thank you for reaching us.