You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: I am Dorothy Hernandez. I want to change my existing reservation. Please help me for that.

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

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

USER: Ok, not an issue. Thanks for the information.

ASSISTANT: Thanks for choosing us.