title: "This field is required." - in django
body: <p>my model</p>
  <pre><code>class User(models.Model):
      lang = models.CharField(max_length=40,choices=LANGUAGE_CHOICES, default='ru')
      email =  models.EmailField((&quot;E-mail&quot;), max_length=254, unique= True)
      user_name = models.CharField((&quot;Имя&quot;),max_length=60)
      phone_number = models.CharField((&quot;Телефон&quot;),max_length=60, unique= True)
      date_of_meeting = models.CharField(max_length=50,choices = DATE_OF_MEETING,default = FIRST)
     
      def __str__(self):
         return &quot;%s %s&quot; % (self.user_name, self.email)
  
  </code></pre>
  <p>my views.py
  I used <code>modelform_factory()</code> in my views to create form without forms.py.</p>
  <pre><code>    class UserView(APIView):
      
      def post(self,request,*args, **kwargs):
          if request.method == 'POST':
              form = modelform_factory(User,  fields=&quot;__all__&quot;)
              response = form(request.POST)
              if response.is_valid():
                  response.save()
                  return JsonResponse(status=status.HTTP_201_CREATED)
              else:
                 return JsonResponse(response.errors, status=status.HTTP_400_BAD_REQUEST)
  </code></pre>
  <p>my post request from postman</p>
  <pre><code>{
      &quot;lang&quot;: &quot;ru&quot;,
      &quot;email&quot;: &quot;asdms@mail.m&quot;,
      &quot;user_name&quot;: &quot;asdasd&quot;,
      &quot;phone_number&quot;: &quot;123123&quot;,
      &quot;date_of_meeting&quot;: &quot;20-11-2021&quot;
  }
  </code></pre>
  <p>After post request I got:</p>
  <pre><code> {
      &quot;lang&quot;: [
          &quot;This field is required.&quot;
      ],
      &quot;email&quot;: [
          &quot;This field is required.&quot;
      ],
      &quot;user_name&quot;: [
          &quot;This field is required.&quot;
      ],
      &quot;phone_number&quot;: [
          &quot;This field is required.&quot;
      ],
      &quot;date_of_meeting&quot;: [
          &quot;This field is required.&quot;
      ]
  }
  </code></pre>
  <p>How to handle that post request correctly and also write in my model? Is this error because of I didn't use serializer?</p>