You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I guide you at present?

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

ASSISTANT: Sure, we are here to help you to change it.

USER: Thank you.

ASSISTANT: Please wait for sometime.

USER: Sure.

ASSISTANT: Thanks for being patient, there was no active reservation on your name.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for opting us.