Message type: E = Error
Message class:  FKK_ID_XX_SAFT - SAFT message 
Message number: 018
Message text: Select the lines you want to change
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The SAP error message FKK_ID_XX_SAFT018 typically occurs in the context of the SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) modules. This error message indicates that the system requires the user to select specific lines or entries before proceeding with a particular action, such as changing or processing data.
Cause: The error is usually triggered when: The user attempts to execute a function that requires specific line items to be selected, but none are selected. The user may have selected an invalid or inappropriate line item for the action they are trying to perform. There may be a configuration issue or a missing prerequisite step that prevents the selection of lines.
Solution: To resolve the error, you can follow these steps: Select Lines: Ensure that you have selected the appropriate line items in the list or table before executing the action. You can usually do this by checking the checkbox next to the relevant entries. Check
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