You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

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

ASSISTANT: Sure, we are glad to help you. May I know your name please?

USER: My name is Sarah Gonzalez.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Sorry we couldn't find any reservation against your name. Thank you for choosing us.

USER: OK, no issues. Thank you.