diff --git a/src/pretix/plugins/sendmail/models.py b/src/pretix/plugins/sendmail/models.py
index e94195a202..197bfa9f0c 100644
--- a/src/pretix/plugins/sendmail/models.py
+++ b/src/pretix/plugins/sendmail/models.py
@@ -19,6 +19,7 @@
 # You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
 # <https://www.gnu.org/licenses/>.
 #
+import logging
 from datetime import datetime, time, timedelta
 
 from dateutil.tz import datetime_exists
@@ -203,7 +204,7 @@ class ScheduledMail(models.Model):
                             continue
 
                         # attendee email available
-                        
+
                         if p.addon_to_id and p.attendee_email == parent_op.attendee_email:
                             # if op is add-on and parent's email match => send to parent
                             p = parent_op
diff --git a/src/pretix/plugins/sendmail/tasks.py b/src/pretix/plugins/sendmail/tasks.py
index f58280ebab..ed82bdf4e5 100644
--- a/src/pretix/plugins/sendmail/tasks.py
+++ b/src/pretix/plugins/sendmail/tasks.py
@@ -31,6 +31,7 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the Apache License 2.0 is
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
+import logging
 from datetime import datetime
 
 from django.db.models import Exists, OuterRef, Q
@@ -43,6 +44,8 @@ from pretix.base.services.mail import mail
 from pretix.base.services.tasks import ProfiledEventTask
 from pretix.celery_app import app
 
+logger = logging.getLogger(__name__)
+
 
 def _chunks(lst, n):
     """