You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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 to check the ticket status?

USER: My name is Michael Mitchell.

ASSISTANT: Ok, please give me a minute.

USER: Ok, I will wait.

ASSISTANT: Sorry to tell you, there is no active reservation found with your name.

USER: Anyway, thanks for the information.

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