Through online research, I found that you can hide 0 (zeros) on a Pie Chart by setting the NumberFormat to “#”.
Thanks for your posting and using Aspose.Cells.
Could you please share with us your actual output excel file and the expected output excel file. You can manually fix your expected output excel file in Microsoft Excel and attach here. It will help us investigate this issue and we will let you know if your issue is fixable or if it is a bug which should be fixed by Aspose.Cells.
Also, if you provide us a sample code that will also facilitate us look into this issue. Thanks for your cooperation.