You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Brenda Thompson. Please, help me in changing my existing reservation as my plan to attend a seminar got postponed.

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there was no reservation found with your given name.

USER: It's ok, not an issue. Thank you for the information.

ASSISTANT: Thank you for opting us.