I routinely get my money back, and other coins as well. You might be able to do the same thing. (Note: I used to fix this stuff for a living, so I learned how they work.)
Step 1: How they work
Step 2: Push the Coin Return knob -- HARD and FAST!
Instead, flick the return knob hard and fast, over and over as fast as you can, and try to fling the coin beyond the edge of the magnet. The coin will drop in to the coin return like it's supposed to do. Repeat as needed. If that doesn't work . . .