I'm going to try to describe the discovery made.
My character kicks and carries boxes, the process of carrying implies that I remove the shape at the time of picking up the box, then takes his box on his head to another place, when he throws his box to the ground, the shape is created again and is assigned to the box.
The error happens with the initial box created in the editor, where the box floats if the player is on top of it, however when throwing the box and creating the new shape that is assigned to that box, the error does not happen.
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