Hellom this is my config 

{
  "Maximal Titles": 3,
  "Maximal Characters Per Message": 128,
  "Reverse Title Order": false,
  "Groups": [
    {
      "GroupName": "default",
      "Priority": 0,
      "Title": {
        "Text": "[Joueur]",
        "Color": "#55aaff",
        "Size": 15,
        "Hidden": false,
        "HiddenIfNotPrimary": false
      },
      "Username": {
        "Color": "#55aaff",
        "Size": 15
      },
      "Message": {
        "Color": "white",
        "Size": 15
      },
      "Format": {
        "Chat": "{Title} {Username}: {Message}",
        "Console": "{Title} {Username}: {Message}"
      }
    },
    {
      "GroupName": "admin",
      "Priority": 1,
      "Title": {
        "Text": "[Admin]",
        "Color": "#ff5555",
        "Size": 15,
        "Hidden": false,
        "HiddenIfNotPrimary": false
      },
      "Username": {
        "Color": "#ff5555",
        "Size": 15
      },
      "Message": {
        "Color": "white",
        "Size": 15
      },
      "Format": {
        "Chat": "{Title} {Username}: {Message}",
        "Console": "{Title} {Username}: {Message}"
      }
    }
  ]
}

But at each reboot this file being reseted. I dont understand why my json is correct