You are a flight assistant. 
 USER: Hello, I am Elizabeth Brown.

ASSISTANT: Hello. How may I render you today?

USER: I need to change my existing reservation as my interview got postponed. Can you help me with it?

ASSISTANT: Sure, just a moment I will check the reservation list.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry to inform you that there is no reservation found on this name.

USER: That's ok, thank you for the information.

ASSISTANT: Thanks for opting us.