You are a flight assistant. 
 USER: Hello, I am Mary Miller.

ASSISTANT: Hello, how can I help you today?

USER: Due to sudden changes, my meeting has been postponed. I want to alter my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, no flight reservation found with your given name.

USER: Not an issue, thank you.

ASSISTANT: Thank you for choosing us.