Luck doesn't work with shulker box

{
    "pools": [
        {
            "rolls": 0,
            "bonus_rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond"

                }
            ]
        },
        {
            "rolls": 0,
            "bonus_rolls": -1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:dirt"

                }
            ]
        }
    ]
}