You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I support you?

USER: I want to change my existing reservation due to prepone of my exams. Can you help me in that?

ASSISTANT: Sure, I am here to aid you.

USER: Thank you.

ASSISTANT: Please mention your good name.

USER: Gregory Thomas here.

ASSISTANT: Ok, please wait for a while.

USER: Ok, take your own time.

ASSISTANT: Thank you for your patience, No reservation was found on your good name.

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

ASSISTANT: Thank you for opting us.