You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: Suddenly, my exam as been changed. So, can you do some changes in my existing reservation?

ASSISTANT: Definitely, I am here to help you with this. Can you please provide your name to change the reservation?

USER: Please, check the previous reservation on Cynthia Martin.

ASSISTANT: Hold on a moment please.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found with the name Cynthia Martin in our database to change the reservation.

USER: That's ok, no issues. Thank you for your help.

ASSISTANT: Thank you for utilising our services.