You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I am Karen Davis. I made a reservation earlier in the wrong date unknowingly so, I want to change my existing reservation. Can you help me in this?

ASSISTANT: Sure, please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found in your name.

USER: It's ok, not a problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.