You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I want to change my existing reservation due to some health issues, can you help me with that?

ASSISTANT: Sure, I can help you.

USER: Thank you.

ASSISTANT: Can I know your name please?

USER: My name is Jack Rodriguez.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Sorry Jack, there is no active reservation found with your name in our records.

USER: No issues, thank you for the information.

ASSISTANT: Most welcome.