You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

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

ASSISTANT: Sure, may I know your name?

USER: Frank Williams here.

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

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you.