You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Dorothy Jackson here.

ASSISTANT: Jackson, how can I aid you today?

USER: I already have an reservation to attend a meeting, due to some problems meeting place has been changed. So I need a few changes in my reservation.

ASSISTANT: Ok, hold on for a moment. Let me check in our data base.

USER: Ok.

ASSISTANT: Sorry Dorothy, there are no flights reserved on your given name formerly.

USER: Ok, thank you for checking.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.