You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Rachel Nelson. I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, I am here to help you in changing the details.

USER: Thank you.

ASSISTANT: Ok, can I put the conversation on hold for a minute?

USER: OK.

ASSISTANT: Sorry to intimate you that, I have not found any previous reservation with your name in our system data.

USER: That's ok, no problem. Thank you.

ASSISTANT: My pleasure.  Thank you for reaching us.