Exception when saving pre-existing Excel file containing Charts

Hello, we have pre-fabricated an Excel file with five charts inside. We open the file, change a few values, then try to save, and get the following exception: System.InvalidCastException: 'Das Objekt des Typs "ComponentPro.Excel.Shapes.ChartShape" kann nicht in Typ "ComponentPro.Excel.WorksheetBase" umgewandelt werden.' Please advise.

Hello Martin, I am not casting anything. I open a file, I change a numeric value in a cell, and I get this error on saving.

Hi, Your are casting object to wrong type . Please check API doc for [Excel][1] [1]: https://doc.componentpro.com/ComponentPro-Excel/ComponentPro-Excel-Charts~Classes