diff --git a/codes/utils/util.py b/codes/utils/util.py
index 2dd3378f..c526fecb 100644
--- a/codes/utils/util.py
+++ b/codes/utils/util.py
@@ -356,7 +356,7 @@ class ProgressBar(object):
 # Recursively detaches all tensors in a tree of lists, dicts and tuples and returns the same structure.
 def recursively_detach(v):
     if isinstance(v, torch.Tensor):
-        return v.detach()
+        return v.detach().clone()
     elif isinstance(v, list) or isinstance(v, tuple):
         out = [recursively_detach(i) for i in v]
         if isinstance(v, tuple):