title: Integrity constraint violation with update permission page
body: <p>I'm using Laratrust Package with laravel 5.5, and I have made a page to create users with their roles and permissions.  This is working well, but the problem is with my update page.  I can't update the value of permissions and I don't know why.</p>
  
  <p>Here is my code for the <strong>update</strong> page:</p>
  
  <pre><code>public function update(Request $request, User $user)
  {
       $request_data = User::find(1);
  
       $request-&gt;validate([
           'name' =&gt; 'required|string|max:255',
          'email' =&gt; 'required|string|email|max:255|unique:users',
  
      ]);
     $request_data=$request-&gt;except(['permissions']);
  
  
      $user-&gt;update($request_data);
       $user-&gt;syncPermissions($request-&gt;permissions);
  
        return redirect('dashboard/index');
  
  }
  </code></pre>
  
  <p>And this is my <strong>edit blade</strong> page:</p>
  
  <pre><code>&lt;form class="m-form m-form--fit m-form--label-align-right m-form--group-seperator" method="post" action="{{ url('dashboard/update/users',$user-&gt;id) }}"&gt;
       {{ csrf_field() }}
       {{ method_field('put') }}
       &lt;div class="m-portlet__body"&gt;           
           &lt;div class="form-group{{ $errors-&gt;has('name') ? ' has-error' : '' }}"&gt;
                          &lt;label for="name" class="col-md-4 control-label"&gt;Name&lt;/label&gt;
  
                          &lt;div class="col-md-6"&gt;
                              &lt;input id="name" type="text" class="form-control" name="name" value="{{ $user-&gt;name }}" required autofocus&gt;
  
                              @if ($errors-&gt;has('name'))
                                  &lt;span class="help-block"&gt;
                                      &lt;strong&gt;{{ $errors-&gt;first('name') }}&lt;/strong&gt;
                                  &lt;/span&gt;
                              @endif
                          &lt;/div&gt;
                      &lt;/div&gt;
  </code></pre>