You are a flight assistant. 
 USER: Hi, I am Anna Thompson.

ASSISTANT: Hello Anna, how can I aid you today?

USER: I want to change my existing reservation as my trip got postponed. Please help me out.

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

USER: OK.

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

USER: No issues, thanks for the information.

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