Mail contact@cpsarena.com — it lands with a human, not a ticket robot.
A device or browser where clicks vanish, double-fire or lag — name the hardware and browser, and paste what the honesty flag said. A technique or input test you want on the site. A score that seems impossible; those are either great stories or great bug reports, and we like both.
We can't adjudicate score disputes between you and your friends (the challenge link makes the test identical; the rest is between you), and we can't diagnose your specific mouse remotely beyond what the checker already measured — its verdict is the best evidence we have to offer.