Error FAGL_POST_SERVICE012 happens in Post Closing step of Actual Costing Run.
"Postings to G/L accounts with open item management are not permitted".
SAP S/4HANA Cloud
Reproducing the Issue
Execute Actual Costing Run - Post Closing step.
From CE2105, with introduction of Parallel Accounting, the material ledger post closing are ledger enabled.
In the new G/L accounting, you can no longer make a direct posting to accounts managed on an open item basis when you use a particular ledger or ledger group.
In SAP Standard it is only possible to create ledger specific postings to non open item managed accounts.
The error is possible happening on revaluation of consumption posting.
The system will find material original account to make the posting.
To find out the configuration, you could use SSCUI 100297 Automatic Account Determination to check the setting for transaction GBB and relevant Valuation Class combination.
Please consider to post to another account without open item management in the future.
FAGL_POST_SERVICE 012, open item, OIM, automatic account determination, parallel accounting, ledger, posting.
KBA , CO-PC-ACT , Actual Costing/Material Ledger , FI-GL , General Ledger Accounting , Problem