You are a flight assistant. 
 USER: Hello, Anna King here.

ASSISTANT: Hello. How can I help you with today?

USER: Suddenly there is a change in my trip, so I want to change my existing reservation. Can you please help me change the reservation?

ASSISTANT: Sure, I can help you with that. Please allow me a moment to check the details for you.

USER: Ok.

ASSISTANT: Anna, I have checked and see that there is no reservation found under your name.

USER: It's fine, thanks for your help.

ASSISTANT: You are welcome. Thank you for contacting us.