diff --git a/project/services/user.py b/project/services/user.py
index 801ec12..69beef7 100644
--- a/project/services/user.py
+++ b/project/services/user.py
@@ -1,5 +1,4 @@
 from flask_security import hash_password
-from sqlalchemy.orm import joinedload
 
 from project import user_datastore
 from project.models import Role, User
@@ -57,6 +56,4 @@ def get_user(id):
 
 
 def find_all_users_with_role(role_name: str) -> list:
-    return (
-        User.query.options(joinedload(User.roles)).filter(Role.name == role_name).all()
-    )
+    return User.query.filter(User.roles.any(Role.name == role_name)).all()
diff --git a/project/views/utils.py b/project/views/utils.py
index a1dbab1..a835819 100644
--- a/project/views/utils.py
+++ b/project/views/utils.py
@@ -124,11 +124,19 @@ def send_mails(recipients, subject, template, **context):
     if len(recipients) == 0:  # pragma: no cover
         return
 
-    msg = Message(subject)
-    msg.recipients = recipients
-    msg.body = render_template("email/%s.txt" % template, **context)
-    msg.html = render_template("email/%s.html" % template, **context)
-    send_mail_message(msg)
+    body = render_template("email/%s.txt" % template, **context)
+    html = render_template("email/%s.html" % template, **context)
+    send_mails_with_body(recipients, subject, body, html)
+
+
+def send_mails_with_body(recipients, subject, body, html):
+    # Send single mails, otherwise recipients will see each other
+    for recipient in recipients:
+        msg = Message(subject)
+        msg.recipients = [recipient]
+        msg.body = body
+        msg.html = html
+        send_mail_message(msg)
 
 
 def send_mail_message(msg):
diff --git a/requirements.txt b/requirements.txt
index 9f17dc2..9064203 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -71,7 +71,7 @@ packaging==20.8
 passlib==1.7.4
 pathspec==0.8.1
 pilkit==2.0
-Pillow==8.3.1
+Pillow==8.3.2
 pluggy==0.13.1
 pre-commit==2.9.3
 psycopg2-binary==2.8.6
diff --git a/tests/api/test_event.py b/tests/api/test_event.py
index 51a2933..1afb1c7 100644
--- a/tests/api/test_event.py
+++ b/tests/api/test_event.py
@@ -534,6 +534,7 @@ def test_report_mail(client, seeder, utils, app, mocker):
     user_id, admin_unit_id = seeder.setup_base(admin=False, log_in=False)
     event_id = seeder.create_event(admin_unit_id)
     seeder.create_user(email="admin@test.de", admin=True)
+    seeder.create_user(email="normal@test.de", admin=False)
 
     mail_mock = utils.mock_send_mails(mocker)
     url = utils.get_url("api_v1_event_reports", id=event_id)
diff --git a/tests/services/test_user.py b/tests/services/test_user.py
new file mode 100644
index 0000000..525785d
--- /dev/null
+++ b/tests/services/test_user.py
@@ -0,0 +1,15 @@
+def test_update_event_dates_with_recurrence_rule(client, seeder, utils, app):
+    user_id, admin_unit_id = seeder.setup_base(admin=False, log_in=False)
+    seeder.create_event(admin_unit_id)
+    admin_id = seeder.create_user(email="admin@test.de", admin=True)
+    seeder.create_user(email="normal@test.de", admin=False)
+
+    with app.app_context():
+        from project.services.user import find_all_users_with_role
+
+        admins = find_all_users_with_role("admin")
+        assert len(admins) == 1
+
+        admin = admins[0]
+        assert admin.id == admin_id
+        assert admin.email == "admin@test.de"
diff --git a/tests/utils.py b/tests/utils.py
index d717ac3..283d280 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -175,28 +175,32 @@ class UtilActions(object):
         )
 
     def mock_send_mails(self, mocker):
-        return mocker.patch("project.views.utils.send_mail_message")
+        return mocker.patch("project.views.utils.send_mails_with_body")
 
-    def assert_send_mail_called(self, mock, recipients, contents=None):
+    def assert_send_mail_called(
+        self, mock, expected_recipients, expected_contents=None
+    ):
         mock.assert_called_once()
         args, kwargs = mock.call_args
-        message = args[0]
+        send_recipients, subject, body, html = args
 
-        if not isinstance(recipients, list):
-            recipients = [recipients]
+        if not isinstance(expected_recipients, list):
+            expected_recipients = [expected_recipients]
 
-            for recipient in recipients:
-                assert recipient in message.recipients, f"{recipient} not in recipients"
+        assert len(send_recipients) == len(expected_recipients)
 
-        if contents:
-            if not isinstance(contents, list):
-                contents = [contents]
+        for expected_recipient in expected_recipients[:]:
+            assert (
+                expected_recipient in send_recipients
+            ), f"{expected_recipient} not in recipients"
 
-            for content in contents:
-                assert content in message.body, f"{content} not in body"
-                assert content in message.html, f"{content} not in html"
+        if expected_contents:
+            if not isinstance(expected_contents, list):
+                expected_contents = [expected_contents]
 
-        return message
+            for content in expected_contents:
+                assert content in body, f"{content} not in body"
+                assert content in html, f"{content} not in html"
 
     def mock_now(self, mocker, year, month, day):
         from project.dateutils import create_berlin_date