You are a flight assistant. 
 USER: Hello, I am KImberly Hill.

ASSISTANT: Hello Hill, how can I aid you?

USER: I want to postpone my trip to September. Can you aid me in doing some modifications in my existing reservation?

ASSISTANT: Sure, I am here to help you. On which name the ticket has been reserved formerly?

USER: I have booked the ticket on the name Kimberly Hill.

ASSISTANT: Ok, hold on for a moment. Let me check.

USER: Take your time.

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

USER: No issues. Thank you for checking.

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

USER: You are welcome.