You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I am Cynthia White and I just want to change an existing reservation due to my health issues. Can you help me with this?

ASSISTANT: Sure, I will help you.

USER: Ok.

ASSISTANT: We didnt found any reservation by this name.

USER: Ok, no problem. Thanks for your help.

ASSISTANT: Thank you.