diff --git a/access/views.py b/access/views.py
index c3e69dd..8cb6305 100644
--- a/access/views.py
+++ b/access/views.py
@@ -128,6 +128,7 @@ class FindUserView(APIView):
 
 class DetailUserView(APIView):
     renderer_classes = (JSONRenderer,)
+    permission_classes = (permissions.IsAuthenticated,)
 
     @staticmethod
     def post(request, out_key=None):
diff --git a/courses/models.py b/courses/models.py
index ce50bf7..eacc7e6 100755
--- a/courses/models.py
+++ b/courses/models.py
@@ -72,7 +72,7 @@ class Topic(models.Model):
 
 class CourseManager(models.Manager):
 
-    def update_or_create_course(self, image=None, big_image=None, statistic=None,
+    def update_or_create_course(self, image=None, big_image=None, statistic=None, old_slug=None,
                                 big_mobile_image=None, slug=None, teacher_tokens=None,
                                 level=None, direction=None, **kwargs):
 
@@ -102,10 +102,11 @@ class CourseManager(models.Manager):
             kwargs['direction'] = get_real_name(COURSE_DIRECTION, direction[0])
 
         try:
-            course = self.get(slug=slug)
+            course = self.get(slug=old_slug)
             for i in kwargs:
                 if kwargs[i]:
                     setattr(course, i, kwargs[i])
+            course.slug = slug
             course.save()
 
         except ObjectDoesNotExist:
diff --git a/finance/models.py b/finance/models.py
index e63f55f..47ac532 100755
--- a/finance/models.py
+++ b/finance/models.py
@@ -6,10 +6,14 @@ from django.core.mail import EmailMessage
 from django.db import models
 from django.utils import timezone
 from yandex_money.models import Payment
+import logging
 
 from progress.models import Progress
 
 
+logger_business_rules = logging.getLogger('business_rules')
+
+
 class Bill(models.Model):
     course_token = models.UUIDField(verbose_name="Токен курса", editable=False)
     user = models.ForeignKey(settings.AUTH_USER_MODEL, verbose_name='Плательщик', related_name='bill_user')
@@ -24,15 +28,22 @@ class Bill(models.Model):
         return '%s: %s' % (self.id, self.user)
 
     def freeze_course(self, user):
-        try:
-            p = Progress.objects.get(user=user, course_token=self.course_token)
-            p.freeze = True
-            p.save()
-        except Progress.DoesNotExist:
-            pass
-
-        self.freeze = True
-        self.save()
+        if self.invoice_set.exclude('F').exists():
+            try:
+                p = Progress.objects.get(user=user, course_token=self.course_token)
+                p.freeze = True
+                p.save()
+            except Progress.DoesNotExist:
+                pass
+
+            self.freeze = True
+            self.save()
+
+        else:
+            logger_business_rules.warning('Попытка нарушения правила отказа от плотежей', exc_info=True, extra={
+                'description': 'Пользоваль пытается отказатся от платежей по счёту, однако все платежи уже оплачены',
+                'user': user,
+            })
 
     def get_full_price(self):
         return sum([i.price for i in self.invoice_set.all() if not i.price is None])
diff --git a/lms/settings.py b/lms/settings.py
index c9f4e61..ce5acd6 100644
--- a/lms/settings.py
+++ b/lms/settings.py
@@ -212,6 +212,11 @@ LOGGING = {
             'class': 'raven.contrib.django.raven_compat.handlers.SentryHandler',
             'tags': {'custom-tag': 'yandex'},
         },
+        'business_rules': {
+            'level': 'DEBUG',
+            'class': 'raven.contrib.django.raven_compat.handlers.SentryHandler',
+            'tags': {'custom-tag': 'business_rules'},
+        },
         'console': {
             'level': 'DEBUG',
             'class': 'logging.StreamHandler',
@@ -228,6 +233,11 @@ LOGGING = {
             'level': 'DEBUG',
             'propagate': False
         },
+        'business_rules': {
+            'handlers': ['business_rules'],
+            'level': 'DEBUG',
+            'propagate': False
+        },
     },
 }
 
diff --git a/progress/views.py b/progress/views.py
index 5b8b2de..97e9b3e 100644
--- a/progress/views.py
+++ b/progress/views.py
@@ -93,6 +93,7 @@ class CourseProgressUserView(APIView):
 
 
 class TeacherUpdateProgress(APIView):
+    permission_classes = (permissions.IsAuthenticated, )
     renderer_classes = (JSONRenderer,)
 
     @staticmethod