Message type: E = Error
Message class:  FI - TR-FM Funds Management 
Message number: 123
Message text: Fiscal year & already posted to. Delete actual data first
You want to reduce the fiscal year timespan for the cash holdings. The
program is now trying to delete the holdings, but Cash Budget
Management still includes actual data in one of the years you want to
delete.
Delete the actual data in Cash Budget Management for the year in
question. When doing so, enter a "to" year, which the system then
automatically adopts as the start year for Cash Budget Management.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FI123 ("Fiscal year & already posted to. Delete actual data first") typically occurs when you attempt to post a financial transaction in a fiscal year that has already been closed or when there are existing postings in that fiscal year. This is a common issue in financial accounting (FI) within SAP, and it is designed to prevent changes to closed periods to maintain the integrity of financial data.
Cause:
Closed Fiscal Year: The fiscal year you are trying to post to has been closed, meaning that no further postings should be made to that year.
Existing Postings: There are already actual postings in the fiscal year you are trying to access, which prevents further entries.
Configuration Settings: The system settings may restrict postings to certain periods based on company policy or accounting standards.
Solution:
Check Fiscal Year Status: Verify if the fiscal year is indeed closed. You can do this by checking Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
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