'Item was not found' when trying to run a command to grant a timed permission from guishop

No idea what i'm doing wrong, or if the plugin still works with guishop, i've tried both "RunCommandAndCustomShopItem": false, and "RunCommandAndCustomShopItem": true, and gathering from old forum posts on oxide that is the proper way of putting in the command, no idea if that's changed or not, the documentation is confusing.

    "Backpack": {
      "DisplayName": "Backpack (24 Hours)",
      "CraftAsDisplayName": false,
      "Shortname": "",
      "ItemId": 0,
      "MakeBlueprint": false,
      "AllowSellOfUsedItems": false,
      "Condition": 0.0,
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "https://w7.pngwing.com/pngs/300/26/png-transparent-dayz-backpack-playerunknown-s-battlegrounds-arma-3-bag-backpack-luggage-bags-military-police-camping-thumbnail.png",
      "SellPrice": 1.0,
      "BuyPrice": 1.0,
      "BuyCooldown": 0,
      "SellCooldown": 0,
      "BuyQuantity": [],
      "SellQuantity": [],
      "BuyLimit": 0,
      "BuyLimitResetCoolDown": 0,
      "SwapLimitToQuantityBuyLimit": false,
      "SellLimit": 0,
      "SellLimitResetCoolDown": 0,
      "SwapLimitToQuantitySoldLimit": false,
      "KitName": "",
      "Command": [
        "grantperm $player.id backpacks.use 24h"
      ],
      "RunCommandAndCustomShopItem": false,
      "GeneTypes": [],
      "SkinId": 0
    },

It might look like this in GuiShop

    "Vip": {
      "DisplayName": "",
      "CraftAsDisplayName": false,
      "Shortname": "",
      "MakeBlueprint": false,
      "AllowSellOfUsedItems": false,
      "Condition": 0.0,
      "EnableBuy": true,
      "EnableSell": false,
      "Image": "",
      "SellPrice": 1.0,
      "BuyPrice": 1.0,
      "BuyCooldown": 0,
      "SellCooldown": 0,
      "BuyQuantity": [],
      "SellQuantity": [],
      "BuyLimit": 0,
      "BuyLimitResetCoolDown": 0,
      "SellLimit": 0,
      "SellLimitResetCoolDown": 0,
      "KitName": "",
      "Command": [
        "grantperm $player.id vip 30d"
      ],
      "RunCommandAndCustomShopItem": false,
      "GeneTypes": [],
      "SkinId": 0
    },