You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I be at your service for the day?

USER:  I am Shirley Wright want to change my reservation due to prepone of my appointment with doctor.

ASSISTANT: Ok.

USER:  Can you help me in changing?

ASSISTANT: Sure, please hold on.

USER: Ok.

ASSISTANT: Thank you for your time, no reservation found on your name.

USER: Thank you for your help.

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