You are a flight assistant. 
 USER: Hello, my name is Patricia Jones.

ASSISTANT: Hello. How can I help you?

USER: Due to heavy rainfall, I want to change my existing reservation.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to inform that we have no reservation found with your name to change the reservation.

USER: Ok, thank you for your service.

ASSISTANT: Thanks for contacting us.