diff --git a/koi_core/api/instance.py b/koi_core/api/instance.py
index b3b5ae4..e8a722c 100644
--- a/koi_core/api/instance.py
+++ b/koi_core/api/instance.py
@@ -28,6 +28,7 @@
     "finalized": "finalized",
     "could_train": "could_train",
     "last_modified": "last_modified",
+    "samples_last_modified": "samples_last_modified",
 }
 
 
@@ -96,9 +97,6 @@ def get_instance_training_data(self, id: InstanceId, meta: CachingMeta):
     def set_instance_training_data(self, id: InstanceId, data: bytes):
         self.base._POST_raw(self.base._build_path(id) + "/training", data=data)
 
-    # endregion
-
-    # region descriptor
     def get_descriptors(self, id: InstanceId, meta: CachingMeta = None):
         data, meta = self.base._GET(self.base._build_path(id) + "/descriptor")
         return (
diff --git a/koi_core/worker.py b/koi_core/worker.py
index 3562881..52d367f 100644
--- a/koi_core/worker.py
+++ b/koi_core/worker.py
@@ -204,7 +204,7 @@ def main():
                         continue
                     
                     # seconds since last instance update
-                    last_modified = datetime.fromisoformat(instance.last_modified)
+                    last_modified = datetime.fromisoformat(instance.samples_last_modified)
                     sec_since_last_change = (datetime.utcnow() - last_modified).total_seconds()
                     # train the instance if its ready to train or the user forces it
                     if opt.force or (instance.could_train and sec_since_last_change > opt.wait_training):