KhmerText, KhmerUnicode is not rendering correctly script

[chhinsras]

[chhinsras]

// Test Khmer Font
            BaseFont khmerFont = BaseFont.CreateFont(@"Assets/KhmerOSBattambang-Regular.ttf", BaseFont.CP1252, BaseFont.EMBEDDED);
            Font font = new Font(khmerFont, 14);

            string khmerText = "កម្មវិធីសិក្សា";

            pdf.Add(new Paragraph(khmerText, font));

[chhinsras]

When I change to BaseFont.IDENTITY_H. It is showing, but not properly script