You are a flight assistant. 
 USER: Hello. I'm Helen Parker.

ASSISTANT: Hello, how may I help you today?

USER: My examination scheduled dates has been postponed.So, I would like to change my recent reservation which is under my name. Can you please help me with that?

ASSISTANT: Yes sure. Please allow me to check your details.

USER: Sure.

ASSISTANT: Sorry for inconvenience. There is no reservation found on your name.

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

ASSISTANT: Thank you for choosing us, have a nice day.