You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Carol Lopez here.

ASSISTANT: How can I assist you Carol Lopez?

USER: I want to change my reservation, due to some health issue. Can you please help me?

ASSISTANT: Sure, I will help you with this.

USER: Thank you.

ASSISTANT: Give me a moment please, let me check the database and get back to you.

USER: Ok.

ASSISTANT: Carol Lopez, there is no active reservation found with your name in our database.

USER: It's ok, thank you for checking.

ASSISTANT: Thank you for contacting us.