Blender Boolean Not working? The difference boolean does nothing on the model
i did check:

face orientations is correct, all blue
merged by distance for all meshes
objects are closed, no holes.

what im trying to do here is cut the 'magma' into this volcano.
The former Boolean bugs as soon as you have overlapping edges, vertices or faces, you need to use the Exact option in the new Blender version and it will work fine: