Minecraft, villager changes his job just like that?

I have turned a zombie villager into a normal villager in my village, to the profession of "clergyman" who has nh purple clothes and his work block is a brewing stand, i have also bought things from him up to the maximum level (5) once he changes his job and all of a sudden his work block becomes the grindstone in my house and he becomes an armorer and i dismantled the grindstone, etc. But it doesn't work.

You can't do anything great about it. This is most likely a bug that will be fixed as villagers normally can't change jobs after trading with them.

Yes, then I'll have to wait