You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: Due to my health conditions, I want to change my recent reservation.Can you help me with that?

ASSISTANT: Sure, I will help you. Sorry to say this, no reservation found under your name in our database.

USER: No problem, Thanks for the information.

ASSISTANT: May I know your name please.

USER: Angela Jones here.

ASSISTANT: Thank you for reaching us.