title: PHP Laravel 5.4.21. Eloquent save insert in first row
body: <p>I have a problem with saving Eloquent models. For example:</p>
  
  <pre><code>$game = Game::select(['bank', 'state', 'quantity_of_players'])-&gt;find($id)-&gt;first();
  $game-&gt;bank += $game-&gt;bet;
  $game-&gt;quantity_of_players++;
  $game-&gt;save();
  </code></pre>
  
  <p>As far as i know from documentation, <code>save()</code> should insert changed values in a row with <code>$id</code>, but instead it inserts in a very first row. What's an issue, and how to save it properly to my database in specified row.</p>
  
  <p>Migration for this model:</p>
  
  <pre><code> public function up()
  {
      Schema::create('games', function (Blueprint $table) {
          $table-&gt;bigIncrements('id');
          $table-&gt;enum('state', ['wait', 'search', 'accept', 'play', 'finish']);
          $table-&gt;smallInteger('quantity_of_players');
          $table-&gt;smallInteger('ready_players');
          $table-&gt;smallInteger('finished_players');
          $table-&gt;integer('bank');
          $table-&gt;smallInteger('bet');
      });
  }
  </code></pre>
  
  <p>Would really appreciate any help with this.</p>
  
  <p>P.S. All <code>SELECT</code> requests works perfectly such as Eloquent <code>create()</code>.</p>