This article provides you with steps on how to fix the problem "Oops, something went wrong" while adding a course catalog admin.
It usually happens when your course catalog is created on a subsite and there is a conflict in inheritance.
By default, all sites, lists, and libraries in a site collection inherit permissions settings from the site that is directly above them in the site hierarchy. This means a site inherits permissions from the root site of the site collection, and a subsite inherits permissions from its parent site, unless you make manually changes to the permissions.
1. View the Permissions page in SharePoint
To view all the unique permissions you have at a site level and delete, please, follow these steps:
1) Go to the Course Catalog site > Gear Icon > Site Permissions > Click Advanced permissions settings:
2) You will notice a message: “Some content on this site has different permissions from what you see here” > Click Show these items > Click manage permissions/view exceptions.
2. Delete unique permissions in SharePoint
Delete unique permissions and restore permission inheritance from a parent. Once you click this button, you will remove all permission changes that you did on this object and repropagate the permission and security settings from the parent:
To learn more about the SharePoint permissions please visit Customize permissions for a SharePoint list or library (microsoft.com).