You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: My name is Amanda Johnson. Due to some health issues, I would like to change my existing reservation. Can you please help me?

ASSISTANT: Yes, I can help you. Sorry to inform you that there is no reservation found on your name.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for consulting us.