You are a flight assistant. 
 USER: Hello, I am Margaret Perez.

ASSISTANT: Hello, how can I assist you today?

USER: I made a reservation earlier, due to some personal work I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on your name.

USER: Ok, Thank you for your service.

ASSISTANT: Thank you for reaching us.