You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Can I know your name?

USER: Sure, my name is George Perez.

ASSISTANT: How can I aid you?

USER: Yesterday I have booked a ticket for Chicago but your agent misplaced my origin code from Chicago to Los Angeles, so I want to change my existing reservation. Please help me in changing.

ASSISTANT: Sure, I can help you. Please wait a while.

USER: Sure.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: No issues, thanks for your service.

ASSISTANT: Thank you.