Solution : https://service.sap.com/sap/support/notes/88691 (SAP Service marketplace login required)
Key words : 
transaction cl02 - 'special functions - delete class, additional key words rmclkdel, inconsistencies/terminations occur, function module cuob_get_object, include message cl156, class type 300, & & class type &, configuration, prerequisites
Related Notes : 
       
| 166530 | @3Z@ Config. objects delete classification data | 
| 151190 | SAP enhancement deletes classification data LO-VC | 
| 88753 |