You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Deborah Lee. Due to my health problem I want to change my reservation, can you please help me to change my reservation?

ASSISTANT: Sure, I am glad to help you to change your reservation.

USER: Thank you.

ASSISTANT: Please hold on for a while.

USER: Ok, I will wait.

ASSISTANT: Sorry, I didn't find any reservation on your name in our database to change your reservation.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us, have a great day.