Too sensitive GameObjects

I am instantiating some cubes one over the other, a number of cubes from 3 to 300. At the game starts the cubes instantiate correctly, but because the gravity thay fall, how can I not change the x and z axes and the rotation of my cubes so that they remain stuck? however, when I go on I will have to move them from the script T$$anonymous$$s is the script that instantiates them T$$anonymous$$s is what should not happen. The poles (gray ones) are not solid, they are only for beauty