You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,. How can I assist you today?

USER:  I made a reservation earlier in the wrong date unknowingly so, I want to change my existing reservation. Can you please help me with that?

ASSISTANT: May i know your name? Sure, I will help you in changing your reservation.

USER: My name is Shirley King.

ASSISTANT: There is no reservation found on your name in our database for changing existing reservation. Thank you for reaching us.

USER: Ok, no issue. Thank you.