You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what service do you require from us?

USER: I'm Emma Johnson. My scheduled examination dates has been postponed.So, I would like to change my existing reservation which is under my name.

ASSISTANT: Ok, I will check for your reservation. Please allow me some time.

USER: Sure.

ASSISTANT: Sorry to tell you Emma, there is no reservation found with your name in our database.

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

ASSISTANT: You are welcome. Thank you for approaching our flight agency. Have a nice day.

USER: You are welcome.