dba_tablespaces column plugged_in missing

Hi,

I am getting an error ORA-904 while executing dbacockpit. I seems, that something is wrong with my dba_tablespaces.

The error is, that column plugged_in is missing.

The error occured after starting the preparations for an upgrade from SAP ERP 6.0 EHP6 to SAP ERP 6.0 EHP7.

I am on Oracle 12c.

Could someone tell me why this column could vanish and how do I get it back?

Best regards

Christian