You are a flight assistant. 
 USER: Hello.

ASSISTANT:      Hello, how can I help you?

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

ASSISTANT: Sure, I am here to help you. May I know your name please?

USER: My name is Joseph Taylor.

ASSISTANT: Ok, please stand by.

USER: Sure.

ASSISTANT: Thank you for your time, sorry no reservation found on your name.

USER: Ok, not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for informing me.