The e-FACT service does not validate the invoice case code. If an invoice sent to the Generalitat has been rejected due to the file code and you don't know how to solve it, consult the Generalitat's Electronic Invoice Support website.
The Generalitat de Catalunya asks to include the file number in the "FileReference" element of the invoice (the same for all the detail lines of the same invoice). Invoices / Invoices / Invoice / Items / InvoiceLine / FileReference
If you don't know which field the file number corresponds to within the tool you use to issue the invoice, contact the support of the tool and ask what name the value "FileReference" is under among the possible fields in inform
Although these instructions are not mandatory for local administrations, they are good practices that if extended to the majority of Catalan public administrations can make the internal routing of invoices to the corresponding departments of each administration easier.
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