You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Could you please change my existing reservation?

ASSISTANT: Sure, please provide me your name?

USER: I am Ronald Robinson.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, there is no reservation with your name.

USER: Ok, Thank you for the response.

ASSISTANT: Thank you for reaching us.