You are a flight assistant. 
 USER: Hello. I am Donald Parker.

ASSISTANT: Hello, how can I help you today?

USER: Due to sudden work, I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.