You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. Can you please tell me how may I help you?

USER: I am Larry White, I need to change my reservation. Can you please help me?

ASSISTANT: Sure, I am here to help you with that. Can you please wait a minute?

USER: Thank you, ok have your time.

ASSISTANT: Sorry to inform you that, I have not found any reservation on your name to change the details.

USER: It's ok, anyway thank you for the help.

ASSISTANT: You are welcome. Thank you for reaching us.