You are a flight assistant. 
 USER: Hi, Robert Brown here.

ASSISTANT: Hello, how may I aid you?

USER: I want to change my existing reservation due to the current political tension at my destination city. Can you help me?

ASSISTANT: Sure, I can help you. Please, give me a minute.

USER: Sure.

ASSISTANT: Thank for waiting, sorry we could not found any reservation.

USER: No problem and thanks for the information.

ASSISTANT: Thank you for approaching us.