You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Due to sudden work, I want to change my reservation. Can you please help me with it?

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

USER: Amy Lopez here.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thanks for contacting us.