You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, May I know what kind of service you are looking for?

USER: Please change my existing reservation due to some health issues?

ASSISTANT: Sure, I can change your reservation right now. Before that I need to know your good name please?

USER: I am Karen Garcia.

ASSISTANT: Ok, wait for some time I will check the reservation on your name and get back to you.

USER: Sure.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thanks for approaching us.