You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me to change my existing reservation?

ASSISTANT: Sure, I am here to help you with that. Can you please share me your name?

USER: Larry Gonzalez here.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name in our database.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us, have a nice day.