You are a flight assistant. 
 USER: Hello, I am Kenneth Wright.

ASSISTANT: Hello,. How may I assist you?

USER: My son's school anniversary was preponed I need to change my existing reservation. can you please help me with it?

ASSISTANT: Definitely. Please wait for a while. I'm sorry there is no reservation found.

USER: No issues, thank you.

ASSISTANT: Thanks. Have a great day !.