The Sharpie needs improvement. Not great at all.
Unfortunately I had the same problem. And I didn't react fast enough to get a free replacement, I hope that the next one(s) work(s)...love the trick, though!
This could be because the Sharpie was not prepared well. I had issues before. Just make sure that the "gimick" is not too out (as the sharpie won't write) or too deep inside that the gimick will not work as it should be. The best way is to push the gimick in a bit and test every time, and repeat until it's perfect.
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