Shape fill is undefined, but should be gradient

Hi Aspose. I have some technical difficulties detecting shape fill type. I made a shape in Powerpoint and made it gradient filled. But the library shows that it’s fill type is undefined. Could you please advise how to detect fill type correctly? Here’s the sample project:
https://drive.google.com/file/d/1p0XZHs1OcZvQixDDsqKzcAC75Qek3e5D/view?usp=sharing

@obrusentsov

Please try using following sample code on your end to serve the purpose.

        using (Presentation pres = new Presentation("clean gradient shape.pptx"))
        {
            foreach (IShape shape in pres.Slides.SelectMany(x=>x.Shapes))
            {
                var ds=shape.CreateFillFormatEffective();
                var fillType2 = ds.FillType;
            }
        }