diff --git a/openslides_backend/action/mixins/linear_sort_mixin.py b/openslides_backend/action/mixins/linear_sort_mixin.py
index a2faef169..a54639700 100644
--- a/openslides_backend/action/mixins/linear_sort_mixin.py
+++ b/openslides_backend/action/mixins/linear_sort_mixin.py
@@ -25,10 +25,14 @@ def sort_linear(
         valid_instance_ids = []
         for id_ in nodes:
             if id_ not in db_instances:
-                raise ActionException(f"Id {id_} not in db_instances.")
+                raise ActionException(
+                    f"{self.model.collection} sorting failed, because element {self.model.collection}/{id_} doesn't exist."
+                )
             valid_instance_ids.append(id_)
         if len(valid_instance_ids) != len(db_instances):
-            raise ActionException("Additional db_instances found.")
+            raise ActionException(
+                f"{self.model.collection} sorting failed, because some elements were not included in the call."
+            )
 
         weight = 1
         for id_ in valid_instance_ids:
diff --git a/tests/system/action/assignment_candidate/test_sort.py b/tests/system/action/assignment_candidate/test_sort.py
index f142f3d06..1088504a5 100644
--- a/tests/system/action/assignment_candidate/test_sort.py
+++ b/tests/system/action/assignment_candidate/test_sort.py
@@ -101,7 +101,10 @@ def test_sort_missing_model(self) -> None:
             {"assignment_id": 222, "candidate_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "assignment_candidate sorting failed, because element assignment_candidate/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -148,7 +151,10 @@ def test_sort_another_section_db(self) -> None:
             {"assignment_id": 222, "candidate_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "assignment_candidate sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_create_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/chat_group/test_sort.py b/tests/system/action/chat_group/test_sort.py
index 5350e223b..51c98ed13 100644
--- a/tests/system/action/chat_group/test_sort.py
+++ b/tests/system/action/chat_group/test_sort.py
@@ -89,7 +89,10 @@ def test_sort_missing_model(self) -> None:
             {"meeting_id": 222, "chat_group_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "chat_group sorting failed, because element chat_group/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_additional_chat_groups_in_meeting(self) -> None:
         self.set_models(
@@ -118,7 +121,10 @@ def test_sort_additional_chat_groups_in_meeting(self) -> None:
             {"meeting_id": 222, "chat_group_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "chat_group sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/motion_category/test_sort_motions_in_categories.py b/tests/system/action/motion_category/test_sort_motions_in_categories.py
index 3dfe9ecf2..b3696c4c0 100644
--- a/tests/system/action/motion_category/test_sort_motions_in_categories.py
+++ b/tests/system/action/motion_category/test_sort_motions_in_categories.py
@@ -50,7 +50,10 @@ def test_sort_missing_model(self) -> None:
             {"id": 222, "motion_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "motion sorting failed, because element motion/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -67,7 +70,10 @@ def test_sort_another_section_db(self) -> None:
             {"id": 222, "motion_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "motion sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permission(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/motion_comment_section/test_sort.py b/tests/system/action/motion_comment_section/test_sort.py
index 1a60e2806..32dc535d2 100644
--- a/tests/system/action/motion_comment_section/test_sort.py
+++ b/tests/system/action/motion_comment_section/test_sort.py
@@ -63,7 +63,10 @@ def test_sort_missing_model(self) -> None:
             {"meeting_id": 222, "motion_comment_section_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "motion_comment_section sorting failed, because element motion_comment_section/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -91,7 +94,10 @@ def test_sort_another_section_db(self) -> None:
             {"meeting_id": 222, "motion_comment_section_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "motion_comment_section sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/motion_state/test_sort.py b/tests/system/action/motion_state/test_sort.py
index f829a2d24..ef4f022d5 100644
--- a/tests/system/action/motion_state/test_sort.py
+++ b/tests/system/action/motion_state/test_sort.py
@@ -38,7 +38,10 @@ def test_sort_extra_id_in_payload(self) -> None:
             {"workflow_id": 1, "motion_state_ids": [3, 2, 4, 1]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 4 not in db_instances." == response.json["message"]
+        assert (
+            "motion_state sorting failed, because element motion_state/4 doesn't exist."
+            == response.json["message"]
+        )
 
     def test_sort_missing_id_in_payload(self) -> None:
         self.set_models(self.permission_test_models)
@@ -47,7 +50,10 @@ def test_sort_missing_id_in_payload(self) -> None:
             {"workflow_id": 1, "motion_state_ids": [3, 1]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." == response.json["message"]
+        assert (
+            "motion_state sorting failed, because some elements were not included in the call."
+            == response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/motion_statute_paragraph/test_sort.py b/tests/system/action/motion_statute_paragraph/test_sort.py
index 919aa9390..e0df7633b 100644
--- a/tests/system/action/motion_statute_paragraph/test_sort.py
+++ b/tests/system/action/motion_statute_paragraph/test_sort.py
@@ -63,7 +63,10 @@ def test_sort_missing_model(self) -> None:
             {"meeting_id": 222, "statute_paragraph_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "motion_statute_paragraph sorting failed, because element motion_statute_paragraph/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -91,7 +94,10 @@ def test_sort_another_section_db(self) -> None:
             {"meeting_id": 222, "statute_paragraph_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "motion_statute_paragraph sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/motion_submitter/test_sort.py b/tests/system/action/motion_submitter/test_sort.py
index c2a78fb60..2c4cc0d81 100644
--- a/tests/system/action/motion_submitter/test_sort.py
+++ b/tests/system/action/motion_submitter/test_sort.py
@@ -45,7 +45,10 @@ def test_sort_missing_model(self) -> None:
             {"motion_id": 222, "motion_submitter_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "motion_submitter sorting failed, because element motion_submitter/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -62,7 +65,10 @@ def test_sort_another_section_db(self) -> None:
             {"motion_id": 222, "motion_submitter_ids": [32, 31]},
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "motion_submitter sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(
diff --git a/tests/system/action/speaker/test_sort.py b/tests/system/action/speaker/test_sort.py
index 221458f6e..776e0f0bd 100644
--- a/tests/system/action/speaker/test_sort.py
+++ b/tests/system/action/speaker/test_sort.py
@@ -43,7 +43,10 @@ def test_sort_missing_model(self) -> None:
             "speaker.sort", {"list_of_speakers_id": 222, "speaker_ids": [32, 31]}
         )
         self.assert_status_code(response, 400)
-        assert "Id 32 not in db_instances." in response.json["message"]
+        assert (
+            "speaker sorting failed, because element speaker/32 doesn't exist."
+            in response.json["message"]
+        )
 
     def test_sort_another_section_db(self) -> None:
         self.set_models(
@@ -59,7 +62,10 @@ def test_sort_another_section_db(self) -> None:
             "speaker.sort", {"list_of_speakers_id": 222, "speaker_ids": [32, 31]}
         )
         self.assert_status_code(response, 400)
-        assert "Additional db_instances found." in response.json["message"]
+        assert (
+            "speaker sorting failed, because some elements were not included in the call."
+            in response.json["message"]
+        )
 
     def test_sort_no_permissions(self) -> None:
         self.base_permission_test(