Message type: E = Error
Message class:  AA - Messages for Asset Accounting 
Message number: 682
Message text: Posting already performed in period &
Posting has already been performed in the period entered.
No processing can take place.
If you want to repeat the depreciation posting in this period, select
the appropriate parameter in the initial request screen. Otherwise,
choose another period.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message AA682 ("Posting already performed in period &") typically occurs in the Asset Accounting (FI-AA) module when you attempt to post a transaction (such as an acquisition, transfer, or retirement) for an asset in a period that has already been closed for posting. This is a safeguard to prevent changes to financial data in periods that have been finalized.
Cause:
Closed Posting Period: The most common cause is that the posting period you are trying to use has already been closed in the financial accounting settings.
Period Locking: The period may be locked for certain types of transactions, preventing any postings from being made.
Incorrect Period: You may be trying to post to a period that is not valid for the asset or the transaction type.
Solution:
Check Posting Periods: Verify the status of the posting periods in the system. You can do this by navigating to the transaction code OB52 (Change Posting
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