First: It may be that the rigid body and the collision body are not set;
The second type: generally because the object to be penetrated is too weak, the problem of collision is not detected at all. In this case, the object can be thickened. But occasionally it doesn't solve the problem, because in this case it is caused by the object moving too fast.
Third; Regarding the problem of the object moving by itself, it is that the object movement script conflicts with the object's character controller (character controller), and it is only necessary to delete the character controller. Of course, there are other situations, that is, the collider of the moving object is embedded in other objects, just fine-tune the collider.
