Message type: E = Error
Message class:  FKK_ID_PT_SIGN - Digital Signature Portugal FI-CA/IS 
Message number: 319
Message text: Interval/Series do not contain checked sequential number &1
The system identified an incossitency in the generation of official
document number or the SAF-T document number. The used sequentional
number is not part of the number range interval that you have defined in
Customizing.
The system aborts the processing.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Customize your system accrodingly in order to create consistent document
numbers.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKK_ID_PT_SIGN319 indicates that there is an issue with the interval or series of numbers in the context of contract accounts or billing documents. Specifically, it means that the system has detected a gap or inconsistency in the sequence of numbers that are expected to be continuous.
Cause: Missing Number: The sequential number that the system is checking for is missing from the defined interval or series. Incorrect Configuration: The number range configuration for the billing documents or contract accounts may not be set up correctly. Manual Interventions: If numbers were manually entered or adjusted, it could lead to gaps in the sequence. Data Migration Issues: If data was migrated from another system, it may not have preserved the correct sequence of numbers.
Solution: Check Number Ranges: Go to the transaction code SNRO (Number Range Objects) and check the configuration for the relevant number range object. Ensure that the intervals are correctly defined and
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