The Hungarian Tax Authority published in the test environment of the platform an update of the API documentation: Online Invoicing System 3.0 Interface Specification adding new ERROR message to be introduced in the Online Invoicing System.
This blocking validation error refers to INVALID_LINE_OPERATION (Error 60) triggered where “MODIFY” is specified in the value of the lineOperation element in an item in the data submission from a modifying or invalidating invoice. Therefore the value of lineOperation must always be “CREATE” for those operations.
Source Sovos
