BPCUI0457W The applications listOfApplications cannot be deleted because they contain subcomponents subcomponent, which cannot be moved up a level in the applications hierarchy due to name conflicts with existing applications in that higher level.

Explanation

When you delete an application, the subcomponents that belong to that application are not automatically deleted unless you specify the Remove subcomponents option. They are moved to the next higher level in the application hierarchy. If those subcomponents have the same name as an application in the higher level, they cannot be moved up, and the parent application of those subcomponents cannot be deleted