To solve the puzzle you must find a way to retrieve the prize behind the window without breaking, altering, or otherwise causing any destruction to the puzzle. The solution does not require brute force, power tools, or persuasive argument.
To open the puzzle, the bottom piece (the piece with the logo) of the puzzle slides off to either side. However, that piece is held in place by a metal pin which comes out of the bottom piece up into the top piece and is held in place by a magnet. So, the solution is to fairly forcefully strike the puzzle against the bottom while also almost simultaneously trying to slide the bottom to either side. You may need to slide it back together upside down so the pin falls when aligned. See pictures below.
Rearrange all of the wooden blocks inside of the box so that there is enough room to place the red block inside.Once complete all blocks will fit comfortably inside the box and the lid should be able to slide closed.