diff --git a/apps/wpm/serializers.py b/apps/wpm/serializers.py
index 74664ef1..49414c67 100644
--- a/apps/wpm/serializers.py
+++ b/apps/wpm/serializers.py
@@ -590,11 +590,15 @@ class MlogbwCreateUpdateSerializer(CustomModelSerializer):
 
     def save_ftest(self, mlogbw, ftest_data):
         if "id" not in ftest_data:
-            ftest = FtestProcessSerializer(data=ftest_data).save()
+            ftest_sr = FtestProcessSerializer(data=ftest_data)
+            ftest_sr.is_valid(raise_exception=True)
+            ftest = ftest_sr.save()
             mlogbw.ftest = ftest
             mlogbw.save()
         else:
-            FtestProcessSerializer(instance=Ftest.objects.get(id=ftest_data["id"]), data=ftest_data).save()
+            ftest_sr = FtestProcessSerializer(instance=Ftest.objects.get(id=ftest_data["id"]), data=ftest_data)
+            ftest_sr.is_valid(raise_exception=True)
+            ftest_sr.save()
         return mlogbw
 
     @transaction.atomic