You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I am Lisa Collins. Can you help me in changing my recent reservation, as my exam is postponed?

ASSISTANT: Sure, please allow me a moment.

USER: Ok.

ASSISTANT: Lisa, there is no reservation found under your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for contacting us.