You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

USER: I want to change my reservation due to health problem, can you help me?

ASSISTANT: Sure, I am here to help you out. Please provide me your name to check previous reservation on your name.

USER: Myself Jennifer Hernandez.

ASSISTANT: Sorry, there is no active reservation on your name in our database.

USER: No problem, thanks for checking.

ASSISTANT: Jennifer Hernandez, thank you for reaching us.