You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Edward Green.

ASSISTANT: Edward Green, how can I aid you today?

USER: I need to change my existing reservation as my plan to go for shopping got postponed. Can you help me?

ASSISTANT: Sure, I am here to help you. Hold on for a moment. Let me check in our data base.

USER: Sure.

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

USER: That's Ok, thanks for your response.

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