You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Lisa Johnson. Can you change my reservation, as my exam is postponed?

ASSISTANT: Sure, I will help you. Please, wait a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.