OSA platform has the history of 5.5 > 6.0 > 7.0 upgrades.
After the upgrade, it does not allow to change login for staff members, the error is shown in CCP:
Error! The unknown error is occured. Please try to use another email as login or contact with support for assistance.
/var/log/pa/core.log the following message can be seen:
Sep 1 15:05:09.972 : ERR [rest:469 1:23585:ac98cb70 SAAS 63736279]: [ APSC] REST Error: PUT /aps/2/application/rest/4b4022fe-5bd3-42fc-984f-db9cf2476150 code=500: 'memberId': can't update property marked as 'final'
The issue is recognized as APS-38141 (Cannot update login: 'memberId': can't update property marked as 'final', caused by incorrect order_num of memberId property).
During 5.5 > 6.0 upgrade, internal property
memberId for staff member APS resources was set incorrectly.
Contact Odin Technical Support to apply the fix in the OA database.