I was trying to edit a user role (System -> Permission -> User Roles) on the magento 2.3.1 admin panel and I started to get this error:
[2019-06-17 08:34:01] main.CRITICAL: Item (Magento\User\Model\User\Interceptor) with the same ID "11" already exists.   [2019-06-17 08:34:01] main.CRITICAL: The "adminhtml.user.editroles" block threw an exception, and it can't be rendered.  
I've tried to google the issue and I've seen similar errors relating to products, however, nothing to do with user roles.
The result of this error is that I see a mostly blank page with no ability to edit the assets that a role has access to.
Appreciate any help.