Planning ODS Load-Errors and Generate Items and Category Sets Keys-Warning after change to item numb

In ERP source instance item number is getting changed from single segment to multiple segment.  Example:  Item current number - T5320ABC is chaing to T5320ABC-BST.

ASCP Collection made after the change in existing instance planning instance errors out in Planning ODS Load request. 

And "Generate Items and Category Sets Keys" request completes in Warning with "ORA-00001: unique constraint (MSC.MSC_ITEM_ID_LID_N2) violated is the error message"

Any help to overcome this will be helpful.

Screen shots of errors with log.