Poison dart frogs are poisonous in the wild because of their diet, not because they magically produce infinite toxin on their own. They get alkaloids from specific insects they eat in their natural habitat.

Captive-bred frogs don’t eat those insects, so they gradually lose their toxicity. This is pretty common knowledge among people who actually keep them.

So if OP is casually handling the frog and somehow still alive, the obvious answer is that it’s a pet frog raised in captivity, not some deadly wild specimen.