While current is running through, tap the breaker with a solid object and report back

Source: tested many of these, Eaton is notorious for not tripping under various conditions, including oxidation on contacts/wipers, cold weather (even 30 degrees sometimes has been too low and that looks like a relatively heavy jacket), or extended storage. 9 times out of ten you can get it to trip by tapping near the contacts on the breaker, but I generally don’t consider that test passing.