On the process of submission of invoices to ZATCA there is a diference when there are lines with 0,00 amount.

The Free Text Invoices are submitted but the Project invoices returns an error related with Tax (even with a Sales tax code, because the base amount is 0 some information of tax is not included on the XML)

It was identified that the diference is on the electronic format on the tag: Item\ClassifiedTaxCategory.

On the eletronic format for that referred tag there is the following condition:

PROJECT INVOICE: AND(NOT(ISEMPTY(@.TaxTrans)), @.TaxTrans.BaseAmount<>0)

FREE TEXT INVOICE:  AND(NOT(ISEMPTY(@.TaxTrans)), @.TaxTrans.TaxCode<>"")

By setup the Project invoice electronic format with the same condition that exists in Free text invoice is possible to submit the Invoice to ZATCA.

Microsoft should review and update the Project electronic format used for ZATCA (SA) in order the XML to include the referred tag for lines with zero amount (for all line types).