diff --git a/src/syngen/ml/worker/worker.py b/src/syngen/ml/worker/worker.py
index 34964b17..040ee40f 100644
--- a/src/syngen/ml/worker/worker.py
+++ b/src/syngen/ml/worker/worker.py
@@ -60,14 +60,14 @@ def __validate_metadata(self):
         validator.run()
         self.merged_metadata = validator.merged_metadata
 
-    def _preprocess_data(self):
+    def _preprocess_data(self, table_name: str):
         """
         Preprocess the data before a training process
         """
         PreprocessHandler(
             metadata=self.metadata,
             metadata_path=self.metadata_path,
-            table_name=self.table_name,
+            table_name=table_name,
             loader=self.loader
         ).run()
 
@@ -338,11 +338,7 @@ def __train_tables(
         delta = 0.49 / len(tables_for_training)
 
         for table in self.metadata.keys():
-            PreprocessHandler(
-                metadata=self.metadata,
-                metadata_path=self.metadata_path,
-                table_name=table
-            ).run()
+            self._preprocess_data(table)
 
         for table in tables_for_training:
             self._train_table(table, metadata_for_training, delta)
diff --git a/src/tests/unit/config/test_config.py b/src/tests/unit/config/test_config.py
index abed3ff0..c57fa670 100644
--- a/src/tests/unit/config/test_config.py
+++ b/src/tests/unit/config/test_config.py
@@ -166,20 +166,20 @@ def test_init_infer_config_with_existed_input_data_in_train_process(mocker, rp_l
     mocker.patch("syngen.ml.data_loaders.DataLoader.has_existed_path", return_value=True)
 
     infer_config = InferConfig(
-            destination="path/to/destination.csv",
-            metadata=metadata,
-            metadata_path="path/to/metadata.yaml",
-            size=100,
-            table_name=table_name,
-            run_parallel=False,
-            batch_size=100,
-            random_seed=None,
-            reports=["accuracy"],
-            both_keys=True,
-            log_level="DEBUG",
-            loader=None,
-            type_of_process="train"
-        )
+        destination="path/to/destination.csv",
+        metadata=metadata,
+        metadata_path="path/to/metadata.yaml",
+        size=100,
+        table_name=table_name,
+        run_parallel=False,
+        batch_size=100,
+        random_seed=None,
+        reports=["accuracy"],
+        both_keys=True,
+        log_level="DEBUG",
+        loader=None,
+        type_of_process="train"
+    )
 
     assert infer_config.reports == ["accuracy"]