You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Samuel Thomas. I would like change my resent reservation because of my health issue. Can you help me in changing my reservation?

ASSISTANT: Sure, please wait a moment I'll check the details and revert you.

USER: Sure.

ASSISTANT: Sorry Samuel, in my database I didn't found any details regarding your reservation.

USER: No issues. Thank you for your support.

ASSISTANT: Thanks for availing us, have a pleasant day.