diff --git a/src/qiboml/backends/pytorch.py b/src/qiboml/backends/pytorch.py
index 7521194..e04d342 100644
--- a/src/qiboml/backends/pytorch.py
+++ b/src/qiboml/backends/pytorch.py
@@ -100,7 +100,7 @@ def issparse(self, x):
         if isinstance(x, self.np.Tensor):
             return x.is_sparse
 
-        return super().issparse(x)
+        return super().is_sparse(x)
 
     def to_numpy(self, x):
         if isinstance(x, list):