diff --git a/bigwig_loader/collection.py b/bigwig_loader/collection.py
index 45b48b2..1d89aab 100644
--- a/bigwig_loader/collection.py
+++ b/bigwig_loader/collection.py
@@ -80,8 +80,10 @@ def reset_gpu(self) -> None:
         """
 
         self._out = cp.zeros((len(self), 1, 1), dtype=cp.float32)
-        del self.__dict__["decoder"]
-        del self.__dict__["memory_bank"]
+        if "decoder" in self.__dict__:
+            del self.__dict__["decoder"]
+        if "memory_bank" in self.__dict__:
+            del self.__dict__["memory_bank"]
 
     @cached_property
     def decoder(self) -> Decoder: