diff --git a/MatrixPlugin.php b/MatrixPlugin.php
index e5f7128863239f8a6fb9cedaeae72561bd53e03f..772e3ff6e28f6096a03370fddfa4ea932a7cd003 100644
--- a/MatrixPlugin.php
+++ b/MatrixPlugin.php
@@ -135,8 +135,8 @@ class MatrixPlugin extends StudIPPlugin implements StandardPlugin
      */
     public function invite($event, $membership)
     {
-        if ($matrix = MatrixAccount::findByUser_id($membership->user_id) &&
-                $room = MatrixRoom::findByRange_id($membership->seminar_id)) {
+        if ($matrix = MatrixAccount::findOneByUser_id($membership->user_id) &&
+                $room = MatrixRoom::findOneByRange_id($membership->seminar_id)) {
             MatrixClient::get()->inviteIntoRoom(
                 MatrixAccount::requireSystemAccount(),
                 $room->getLinkedRoom(),
@@ -153,8 +153,8 @@ class MatrixPlugin extends StudIPPlugin implements StandardPlugin
      */
     public function uninvite($event, $membership)
     {
-        if ($matrix = MatrixAccount::findByUser_id($membership->user_id) &&
-            $room = MatrixRoom::findByRange_id($membership->seminar_id)) {
+        if ($matrix = MatrixAccount::findOneByUser_id($membership->user_id) &&
+            $room = MatrixRoom::findOneByRange_id($membership->seminar_id)) {
             MatrixClient::get()->leaveRoom(
                 $matrix->getLinkedAccount(),
                 $room->getLinkedRoom()
@@ -171,7 +171,7 @@ class MatrixPlugin extends StudIPPlugin implements StandardPlugin
      */
     public function unregister($event, $user)
     {
-        if ($account = MatrixAccount::findByUser_id($user->id)) {
+        if ($account = MatrixAccount::findOneByUser_id($user->id)) {
             if (MatrixClient::get()->deactivateAccount($account->getLinkedAccount())) {
                 $account->delete();
             }
@@ -186,7 +186,7 @@ class MatrixPlugin extends StudIPPlugin implements StandardPlugin
      */
     public function deleteRoom($event, $course)
     {
-        if ($room = MatrixRoom::findByRange_id($course->id)) {
+        if ($room = MatrixRoom::findOneByRange_id($course->id)) {
             MatrixClient::get()->deleteRoom(
                 MatrixAccount::requireSystemAccount(),
                 $room->getLinkedRoom()
diff --git a/plugin.manifest b/plugin.manifest
index 23e71f49e7c459f3371ddd781f55427cd9307647..c25c2a6303033a7bb5dfd65b1c046dbff63a10fb 100644
--- a/plugin.manifest
+++ b/plugin.manifest
@@ -1,7 +1,7 @@
 pluginname=Matrix-Chat
 pluginclassname=MatrixPlugin
 origin=data-quest
-version=1.4.2
+version=1.4.3
 screenshot=assets/images/matrix_logo.png
 description=Matrix chat for Stud.IP courses
 studipMinVersion=4.5