TypeError 

  explode(): Argument #2 ($string) must be of type string, Closure given

  at vendor\laravel\framework\src\Illuminate\Collections\helpers.php:52
     48▕         if (is_null($key)) {
     49▕             return $target;
     50▕         }
     51▕
  ➜  52▕         $key = is_array($key) ? $key : explode('.', $key);
     53▕
     54▕         foreach ($key as $i => $segment) {
     55▕             unset($key[$i]);
     56▕

  1   vendor\laravel\framework\src\Illuminate\Collections\helpers.php:52
  2   vendor\laravel\framework\src\Illuminate\Collections\Arr.php:700