diff --git a/src/pruna/config/smash_config.py b/src/pruna/config/smash_config.py
index 9d1ae6b0..ba277633 100644
--- a/src/pruna/config/smash_config.py
+++ b/src/pruna/config/smash_config.py
@@ -286,10 +286,14 @@ def load_from_json(self, path: str | Path) -> None:
         saved_values = {k: v for k, v in config_dict.items() if k in supported_hparam_names}
 
         # Seed with the defaults, then overlay the saved values
-        default_values = dict(SMASH_SPACE.get_default_configuration())
-        default_values.update(saved_values)
-
-        self._configuration = Configuration(SMASH_SPACE, values=default_values)
+        self._configuration = SMASH_SPACE.get_default_configuration()
+        # activate all algorithms already in the space to make children hyperparameters appear
+        saved_algorithm_keys = set(self._configuration.keys()) & set(saved_values.keys())
+        for key in saved_algorithm_keys:
+            self._configuration[key] = True
+        # register all saved hyperparameters
+        for key, value in saved_values.items():
+            self._configuration[key] = value
 
         tokenizer_path = Path(path) / TOKENIZER_SAVE_PATH
         if tokenizer_path.exists():