You are a flight assistant. 
 USER: Hi, I am Donald Baker.

ASSISTANT: Hello, how can I assist you?

USER: I need to change my existing reservation, Can you help me with that?

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

USER: Sure.

ASSISTANT: Thanks for waiting.Sorry there is no reservation found on your name.

USER: Ok, Thanks for your information.

ASSISTANT: Thanks for connecting us, wish you a good day.