You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Raymond Brown.

ASSISTANT: How can I assist you today?

USER: Due to some health issues, I couldn't travel. Can you please change my existing reservation?

ASSISTANT: Sure, Definitely I'll help you in that. Please be on hold while I'll check your reservation status.

USER: Sure.

ASSISTANT: Brown, there is no reservation found under your name to do changes in that.

USER: Its ok, no issues. Thank you for the information.

ASSISTANT: Thank you for choosing us.