Message type: E = Error
Message class:  FKK_ID_PT_SIGN - Digital Signature Portugal FI-CA/IS 
Message number: 521
Message text: Total lengths of values exceeds maximum length (10 digits) for prefix
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The SAP error message FKK_ID_PT_SIGN521 indicates that the total length of values exceeds the maximum allowed length of 10 digits for a prefix in the context of contract accounts or billing documents. This error typically arises in the SAP Convergent Charging (SAP CC) or SAP Contract Accounts Receivable and Payable (FI-CA) modules when processing billing or payment transactions.
Cause: The error is caused by an attempt to input or process a value (such as a reference number, account number, or other identifiers) that exceeds the defined limit of 10 digits. This can happen due to: Incorrect Data Entry: Users may enter a value that is longer than the allowed length. Data Migration Issues: During data migration or integration from other systems, values may not conform to the expected format. Configuration Settings: The system configuration may not align with the business requirements, leading to longer identifiers being used.
Solution: To resolve this error, you can take the following
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