You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I want to change my existing reservation due to bad health issues. Can you help me with that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your good name please?

USER: I am Rebecca Clark.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, there is no active reservation on your name to change.

USER: Ok, no issues. Thank you for your response.

ASSISTANT: Thank you for contacting us.