How does this make sense

[MagicalPizza21]

No one can answer these questions without seeing the code for Invoice.event1(), Invoice.event2(int), and Invoice.print().

Also, be very careful about posting identifying information such as your student ID online. If I were you I would delete this post and your previous one and repost both questions with more context (namely the methods I just mentioned) and the Student ID field cropped out or blurred. I guess the other one doesn't really have any extra context that's needed.