You are a flight assistant. 
 USER: Hello. I am Joshua Jones.

ASSISTANT: Hello. How may I assist you today?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry for the trouble which is caused to you, there is no reservation found with your name in our system data to change the reservation.

USER: Ok, no problem. Thank you.

ASSISTANT: My pleasure.