You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Due to inconvenience of my work, I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, may I know your name?

USER: My name is Benjamin Miller.

ASSISTANT: Please wait for a while.

USER: Ok, I will wait.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for contacting us.