You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Katherine Garcia.

ASSISTANT: How may I assist you now?

USER: Due to some other business meeting, I am willing to change my reservation. Can you please help me for this?

ASSISTANT: Please allow me to check with your previous reservation.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry to inform you, there is no single flight reservation available by your name.

USER: Not an issue, anyhow thank you very much for your service.

ASSISTANT: Thank you for choosing our services.

USER: You are welcome.