diff --git a/python/dgl/graphbolt/impl/gpu_cached_feature.py b/python/dgl/graphbolt/impl/gpu_cached_feature.py
index 09c960b7fb39..94c3a97b0b6d 100644
--- a/python/dgl/graphbolt/impl/gpu_cached_feature.py
+++ b/python/dgl/graphbolt/impl/gpu_cached_feature.py
@@ -95,7 +95,7 @@ def read_async(self, ids: torch.Tensor):
         for _ in range(
             self._fallback_feature.read_async_num_stages(missing_keys.device)
         ):
-            missing_values_future = next(fallback_reader)
+            missing_values_future = next(fallback_reader, None)
             yield  # fallback feature stages.
         values[missing_index] = missing_values_future.wait()