diff --git a/rest_auth/serializers.py b/rest_auth/serializers.py
index b6452317..a438d392 100644
--- a/rest_auth/serializers.py
+++ b/rest_auth/serializers.py
@@ -3,8 +3,8 @@
 from django.contrib.auth.forms import PasswordResetForm, SetPasswordForm
 from django.contrib.auth.tokens import default_token_generator
 from django.utils.http import urlsafe_base64_decode as uid_decoder
-from django.utils.translation import ugettext_lazy as _
-from django.utils.encoding import force_text
+from django.utils.translation import gettext_lazy as _
+from django.utils.encoding import force_str
 
 from rest_framework import serializers, exceptions
 from rest_framework.exceptions import ValidationError
@@ -205,7 +205,7 @@ def validate(self, attrs):
 
         # Decode the uidb64 to uid to get User object
         try:
-            uid = force_text(uid_decoder(attrs['uid']))
+            uid = force_str(uid_decoder(attrs['uid']))
             self.user = UserModel._default_manager.get(pk=uid)
         except (TypeError, ValueError, OverflowError, UserModel.DoesNotExist):
             raise ValidationError({'uid': ['Invalid value']})
@@ -256,8 +256,7 @@ def validate_old_password(self, value):
         )
 
         if all(invalid_password_conditions):
-            err_msg = _("Your old password was entered incorrectly. Please enter it again.")
-            raise serializers.ValidationError(err_msg)
+            raise serializers.ValidationError('Invalid password')
         return value
 
     def validate(self, attrs):