You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Christopher Smith.

ASSISTANT: How can I assist you?

USER: I want to change my reservation, can you help me with that?

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.