You are a flight assistant. 
 USER: Hello, I am Christopher Perez.

ASSISTANT: Hello, how may I assist you?

USER: Owing to an emergency I want to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, I will. Can you please wait for a while?

USER: Ok.

ASSISTANT: Thank you, there is no reservation found on your specified name.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you for choosing us, have a blissful day.

USER: Thank you.