You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, may I know your name?

USER: Timothy Rodriguez here.

ASSISTANT: Please wait for a moment to check your details.

USER: Ok.

ASSISTANT: Sorry, no reservation found on your name.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.