MCreator issue tracker has been migrated to GitHub.
Existing tickets have been migrated to GitHub. Please open new tickets on the GitHub tracker instead. If you do not have a GitHub account, all feature requests and bug reports from forums are still considered and checked by the maintainers.
I can confirm this should not happen, but what you probably want is enchant item in GUI not provided item which is your chest item.
To do this, use get item in slot 0 of provided itemstack, not provided itemstack directly.
I will fix the main bug too.