You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name please?

USER: I'm Ronald Phillips, can you please help me to change my existing reservation?

ASSISTANT: Sure, please wait for a moment. Sorry, do you have the reservation with this name?

USER: Ok, fine thank you for your information.

ASSISTANT: There is no reservation found by your provided name.

USER: Thank you for your information.

ASSISTANT: Thank you and have a nice day.