https://userapps.support.sap.com/sap/support/knowledge/en/3594448
3594448 - Error KF438 & KF439 for dependent characteristics in KEU2 or KEU3 | SAP Knowledge Base...
When attempting to navigate between segments of a CO-PA assessment cycle in transaction KEU2 or KEU3, error messages KF438 and KF439 is displayed. The error...