diff --git a/tests/test_fsm/storage/test_isolation.py b/tests/test_fsm/storage/test_isolation.py
index 8be303c4..1fb21d55 100644
--- a/tests/test_fsm/storage/test_isolation.py
+++ b/tests/test_fsm/storage/test_isolation.py
@@ -53,7 +53,7 @@ class TestRedisEventIsolation:
             assert isolation.redis is not None
             assert isolation.key_builder is not None
 
-            assert pool.called_once_with("redis://localhost:6379/0")
+            pool.assert_called_once_with("redis://localhost:6379/0")
 
     async def test_close(self):
         isolation = RedisEventIsolation(redis=AsyncMock())