when I activate it, the villager still locked, and when I trade a new item it lock anyways
I dont know what is happpening, I play in ssp world
it not fuction with some villager

It may have broken with some recent Minecraft updates. I haven't actually tested or verified it in a long time.

The current implementation of that feature is actually pretty bad, and I would recommend not using it at all until I rewrite it at some point, because it modifies the trade counts in the villager in a way that you can't easily turn it off "immediately".