diff --git a/CHANGELOG.md b/CHANGELOG.md
index f95614b4..10206ede 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -29,6 +29,7 @@ This release closes the [2.2.0 milestone](https://github.com/Instagram/IGListKit
 
 - Fix bug where emptyView's hidden status is not updated after the number of items is changed with `insertInSectionController:atIndexes:` or related methods. [Peter Edmonston](https://github.com/edmonston) [(#395)](https://github.com/Instagram/IGListKit/pull/395)
 - Fix bug where `IGListStackedSectionController`'s children need to know `numberOrItems` before didUpdate is called. [(#348)](https://github.com/Instagram/IGListKit/pull/390)
+- Fix bug where `-[UICollectionViewCell ig_setStackedSectionControllerIndex:]` should use `OBJC_ASSOCIATION_COPY_NONATOMIC` for NSNumber. [PhilCai](https://github.com/PhilCai1993) [(#424)](https://github.com/Instagram/IGListKit/pull/426)
 
 2.1.0
 -----
@@ -178,3 +179,5 @@ You can find a [migration guide here](https://instagram.github.io/IGListKit/migr
 -----
 
 Initial release. :tada:
+
+
diff --git a/Source/IGListStackedSectionController.m b/Source/IGListStackedSectionController.m
index 0d590b43..1496998f 100644
--- a/Source/IGListStackedSectionController.m
+++ b/Source/IGListStackedSectionController.m
@@ -33,7 +33,7 @@ static void * kStackedSectionControllerKey = &kStackedSectionControllerKey;
 static void * kStackedSectionControllerIndexKey = &kStackedSectionControllerIndexKey;
 
 - (void)ig_setStackedSectionControllerIndex:(NSInteger)stackedSectionControllerIndex {
-    objc_setAssociatedObject(self, kStackedSectionControllerIndexKey, @(stackedSectionControllerIndex), OBJC_ASSOCIATION_ASSIGN);
+    objc_setAssociatedObject(self, kStackedSectionControllerIndexKey, @(stackedSectionControllerIndex), OBJC_ASSOCIATION_COPY_NONATOMIC);
 }
 
 - (NSInteger)ig_stackedSectionControllerIndex {