diff --git a/.github/workflows/migrations.yaml b/.github/workflows/migrations.yaml
index 35a7c6b..26feddd 100644
--- a/.github/workflows/migrations.yaml
+++ b/.github/workflows/migrations.yaml
@@ -45,7 +45,7 @@ jobs:
           CHANGED_MIGRATION_FILES: ${{ steps.migration-changes.outputs.all_changed_files }}
         run: |
           if [[ -n "$CHANGED_MODEL_FILES" && -z "$CHANGED_MIGRATION_FILES" ]]; then
-            echo "Model Chages detected, but no corresponding migration changes."
+            echo "Model Chages detected, but no corresponding migration changes. Create the corresponding migrations."
             exit 1
           fi
 
@@ -55,3 +55,16 @@ jobs:
           fi
           
           echo "Changes look valid."
+
+  prevent-changes:
+    run: |
+      EXISTING_MIGRATIONS=$(git ls-tree -r HEAD --name-only | grep "core/alembic/versions/.*\.py")
+
+      for migration in $EXISTING_MIGRATION; do
+        if git diff --name-only HEAD | grep "$migration"; then
+          echo "An already existing migration should not be edited!"
+          exit 1
+        fi
+      done
+
+
diff --git a/core/alembic/versions/11cb4f286ec5_create_user_table.py b/core/alembic/versions/11cb4f286ec5_create_user_table.py
index cc7f43b..c727208 100644
--- a/core/alembic/versions/11cb4f286ec5_create_user_table.py
+++ b/core/alembic/versions/11cb4f286ec5_create_user_table.py
@@ -29,6 +29,7 @@ def upgrade() -> None:
         sa.PrimaryKeyConstraint("uuid"),
         sa.UniqueConstraint("email"),
     )
+    print("edit")
     # ### end Alembic commands ###
 
 
diff --git a/core/services/test_service/models/test_two.py b/core/services/test_service/models/test_two.py
deleted file mode 100644
index b7032a1..0000000
--- a/core/services/test_service/models/test_two.py
+++ /dev/null
@@ -1,2 +0,0 @@
-test = "hi"
-print(test)
diff --git a/core/services/user_service/models/test.py b/core/services/user_service/models/test.py
deleted file mode 100644
index 8a49ce5..0000000
--- a/core/services/user_service/models/test.py
+++ /dev/null
@@ -1,2 +0,0 @@
-test = "hallo"
-print(test)