You are a flight assistant. 
 USER: Hello. I am Shirley Allen.

ASSISTANT: Hello, how can I help you?

USER:  I have planned to consult a doctor for monthly check up due to more emergency operations scheduled to him my appointment has been changed.  can you help me in changing my reservation?

ASSISTANT: Sure, I am here to help you. Please wait a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry we didn't find any reservation on your name.

USER: Ok, no issues. Thank you for helping me.

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