I don't know why, but in my current project with TypeScript, there were two rules for unused vars.

 "no-unused-vars": [
      "error",
      {
        "vars": "all",
        "args": "after-used",
        "ignoreRestSiblings": false
      }
    ],
    "@typescript-eslint/no-unused-vars": [
      "error",
      {
        "vars": "all",
        "args": "after-used",
        "ignoreRestSiblings": false
      }
    ],

So basically they conflicted with each other and sometimes throw incorrect errors. The solution for this kind of problem is:

 "no-unused-vars": "off",
 "@typescript-eslint/no-unused-vars": ["error"]

After this, my ESLint started working just perfect :)

Thank you.