You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I am Catherine Lopez, can you please help me in changing my reservation as my trip got postponed due to some health problem?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

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

USER: No worries, thank you for your time.

ASSISTANT: Thank you for choosing us.