diff --git a/src/olympia/blocklist/mlbf.py b/src/olympia/blocklist/mlbf.py
index fa3b20e8740a..7fa89f0e1fbb 100644
--- a/src/olympia/blocklist/mlbf.py
+++ b/src/olympia/blocklist/mlbf.py
@@ -111,15 +111,15 @@ def __init__(self, storage: SafeStorage):
 
     @cached_property
     def blocked_items(self) -> List[str]:
-        return self._data.get(self.data_type_key(MLBFDataType.BLOCKED), [])
+        return self._data.get(MLBF.data_type_key(MLBFDataType.BLOCKED), [])
 
     @cached_property
     def soft_blocked_items(self) -> List[str]:
-        return self._data.get(self.data_type_key(MLBFDataType.SOFT_BLOCKED), [])
+        return self._data.get(MLBF.data_type_key(MLBFDataType.SOFT_BLOCKED), [])
 
     @cached_property
     def not_blocked_items(self) -> List[str]:
-        return self._data.get(self.data_type_key(MLBFDataType.NOT_BLOCKED), [])
+        return self._data.get(MLBF.data_type_key(MLBFDataType.NOT_BLOCKED), [])
 
 
 class MLBFDataBaseLoader(BaseMLBFLoader):