Tutorial doesn't advance when breaking nether tree

Did you tried to break it with your hand?

it should work, nonetheless, right? (that advancement stays forever, maybe i feel like the tree isn't counted as a tree to make an advancement)

It's not an advancement. That's the tutorial banner. The game is getting confused because it thinks you're a new player. I'm assuming it doesn't count nether trees because new players aren't going to start in the nether.

oh, thanks for clearing the issue, i found a fix just by re-entering the same world.