Message type: E = Error
Message class:  PSSC_BILLING - PS Social Services - Billing 
Message number: 121
Message text: Contract account category &1 not found
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The SAP error message PSSC_BILLING121 indicates that the system could not find a contract account category specified in the transaction. This error typically occurs in the context of billing or contract account management within SAP, particularly in the SAP Convergent Charging (SAP CC) or SAP Convergent Invoicing (SAP CI) modules.
Cause: Incorrect Contract Account Category: The contract account category specified in the transaction does not exist in the system. This could be due to a typo or an incorrect configuration. Missing Configuration: The contract account category may not have been set up in the system. This can happen if the necessary configuration steps were not completed during the implementation or if the category was deleted or deactivated. Data Migration Issues: If data was migrated from another system, there may have been issues with the mapping of contract account categories.
Solution: Check Configuration: Go to the configuration settings in SAP and verify that the contract account category exists.
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