Message type: E = Error
Message class:  FINS_FI_SIF - SAP S/4HANA Finance: Subsequent Implementation of Functions 
Message number: 203
Message text: CompCode &1 was already entered in SrcLdgr &2. Change existing entry.
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The SAP error message FINS_FI_SIF203 indicates that there is a duplicate entry for a company code (CompCode) in a source ledger (SrcLdgr). This typically occurs during the process of data entry or data migration when the system detects that the specified company code has already been recorded in the specified source ledger.
Cause: Duplicate Entry: The primary cause of this error is that the company code you are trying to enter already exists in the source ledger you are working with. Data Migration Issues: If you are migrating data from one system to another, it is possible that the data being imported contains duplicates. Incorrect Data Entry: Users may inadvertently attempt to enter the same company code multiple times.
Solution: Check Existing Entries: Review the entries in the specified source ledger to confirm if the company code is already present. You can do this by navigating to the relevant transaction or report that displays the entries
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