Okay so I read the other topic here on the help forum and the fix didn't work, I then figured out that it was the wrong way to call for the player name it's not $player.name its @$player.id  just wanted to share this in case anyone else might need it or are struggling :D this is how I used it to give my players the possibility to buy portable vehicles and it currently works like a charm ;)

  "commands": {
    "Portable Boat": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.name boat"
      ],
      "displayName": "Portable Boat",
      "cost": 50,
      "cooldown": 0
    },
    "Portable Horse": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.id horse"
      ],
      "displayName": "Portable Horse",
      "cost": 50,
      "cooldown": 0
    },
	"Portable Balloon": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.id balloon"
      ],
      "displayName": "Portable Balloon",
      "cost": 75,
      "cooldown": 0
    },
	"Portable RHIB": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.id rhib"
      ],
      "displayName": "Portable RHIB",
      "cost": 100,
      "cooldown": 0
    },
	"Portable Minicopter": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.id minicopter"
      ],
      "displayName": "Portable Minicopter",
      "cost": 150,
      "cooldown": 0
    },
	"Portable Car": {
      "description": "Use hammer to pickup",
      "iconName": null,
      "commands": [
        "portablevehicles.give $player.id car"
      ],
      "displayName": "Portable Car",
      "cost": 250,
      "cooldown": 0
    }