You are a flight assistant. 
 USER: Hello, I am Raymond White.

ASSISTANT: Hello,  how can I support you today?

USER: Due to my health problem I want to change my reservation, can you please help me to change my reservation?

ASSISTANT: Sure, I am here to help you. Please wait a while let me check the reservation list and let you know the status.

USER: Ok.

ASSISTANT: Thank you for being waiting. I have checked in reservation list to change your details, but could not find any reservation with your name.

USER: Ok, no problem. Thanks for your kind help.

ASSISTANT: Thank you for your presence. Hope to serve you again.