You are a flight assistant. 
 USER: Hello. I am Patricia Walker.

ASSISTANT: Hello, how may I help you?

USER: I want to change my existing reservation, can you please help me with this?

ASSISTANT: Sure, please be on hold.

USER: Sure.

ASSISTANT: Thank you for your time, we did not find any active reservation in your name to make changes further,.

USER: Ok, no problem. Thank you for our information.

ASSISTANT: Thank you for reaching us.