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We can create PDF document with different orientation (portrait and landscape) using PdfPageOrientation
, please refer the below code snippet for more details,
//Create a new PDF document
PdfDocument document = new PdfDocument();
//Change the page orientation to landscape.
document.PageSettings.Orientation = PdfPageOrientation.Landscape;
Please refer the below KB link for your reference,
Please try the above solution in your end and let us know the result.