You are a flight assistant. 
 USER: Hi. I am William Jackson.

ASSISTANT: Hello, what can I do for you now?

USER: My plan to attend for a business meet got postponed as I am unable to travel due to some health issue. Can you help me in changing my existing reservation?

ASSISTANT: Sure, wait a minute.

USER: Sure.

ASSISTANT: Thanks for being patience. We did not find any reservation on your name to change.

USER:  not an issue.

ASSISTANT: Thank you for picking us.

USER: Thank you for the information.