title: User profile info(table) with this Cpf cnpj(field (unique)) already exists
body: <p>My View code is this: </p>
  
  <pre><code> @login_required
      def DadosUserView(request):
          template_name = 'users_c2p/dados.html'
          usercpf = request.user.username
          profile = UserProfileInfo.objects.filter(cpf_cnpj=usercpf)
          contrato_dividas = Contrato.objects.filter(cpf_cnpj=usercpf)
          empresa = Empresa.objects.all()
          if profile:
              person = get_object_or_404(UserProfileInfo, cpf_cnpj=usercpf)
              profile_form = UserProfileInfoForm(request.POST or None, instance=person)
              flag = 1
          else:
              profile_form = UserProfileInfoForm(initial={"cpf_cnpj": usercpf,
                                                          })
              flag = 0
          if request.method == 'POST':
              profile_form = UserProfileInfoForm(data=request.POST)
              print(request.method)
              print(profile_form.errors)
              if profile_form.is_valid():
                  # Create new profile
                  if flag == 0:
                          profile_form_cpf = profile_form.cleaned_data['cpf_cnpj']
                          print(profile_form_cpf)
                          if usercpf == profile_form_cpf:
                              profile_form.save()
                              log = LogUsuario.objects.create(cpf_cnpj=profile_form_cpf, movimentacao="FIRST UPDATE")
                              return redirect(reverse_lazy('users_c2p:dadosuser'))
                          else:
                              return profile_form.errors
                  #Update profile
                  elif flag == 1:
                      profile_form_cpf = profile_form.cleaned_data['cpf_cnpj']
                      if usercpf == profile_form_cpf:
                          profile_form.save()
                          log = LogUsuario.objects.create(cpf_cnpj=profile_form_cpf, movimentacao="UPDATE")
                          return redirect(reverse_lazy('users_c2p:sucesso_cadastro'))
                      else:
                          return profile_form.errors
              else:
                  return redirect(reverse_lazy('users_c2p:dadosuser'))
          context = {
                      "UserData" : profile,
                      "profile_form": profile_form,
                      "Contrato": contrato_dividas,
                      "Empresa": empresa,
                      #'media_url': settings.MEDIA_URL,
                    }
          return render(request, template_name, context)
  </code></pre>
  
  <p>I want to user the #Update profile part..
  The #Create profile is working well, but when I try to update it, it says that user already exists and do nothing.</p>
  
  <p>What should I do, so it recognizes this is the idea and then update the info that I desire?</p>