You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I need to change my existing reservation due to my exams, can you help me in doing that?

ASSISTANT: Sure, I am here to help you with that, may I know your name to proceed further?

USER: Ryan Campbell here.

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

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.