You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you at this moment?

USER: My name is Ronald Jackson and I would like to change an existing reservation.

ASSISTANT: I will help you about that Ronald Jackson.

USER: Sure, please.

ASSISTANT: Please be on hold to check the reservation status with your name in our booking list.

USER: Sure.

ASSISTANT: I regret to say this Ronald Jackson, there is no active reservation with your name to change your reservation.

USER: No problem, thank you for the information.

ASSISTANT: You are welcome, thank you for reaching us. Hope you have a nice day ahead.