How i rest damage to an item without damaging the entire item class? (1.20.1)

So, basicaly, i made a new item class for mi mod, and it's used on a block as a requirement to crafting items. I tried to do damage to the individual item, but instead aplies the damage to all items of his class. Example: i have a "stone polisher" with a MaxDamage of 200, if i do 20 damage per craft, it will be rested to all "stone polisher" items in game instead of the individual item that is placed on the block. I tried almost everything that i can imagine, i read the TieredItem class and all his child classes, but anything of that helped me.