flypig@h_witteborn I've been using these covers myself daily for over a year and not had any trouble, but I'm sorry it didn't turn out as you were expecting.
I've uploaded a new design that's slightly thicker (by 0.5mm on the top, same width on the sides): http://shpws.me/MkO2
If you post me your original, I'll order you this thicker variant to try (please DM to arrange).
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