Hi Amir
Thanks for using Syncfusion products.
We have analyzed your query and we suspect that nuget not referred properly in sample. Please make sure that below highlighted dlls are referred correctly in sample application.
Screenshot :
Please refer below user documentation for more details about download and install.
Please refer below user documentation about more details about SfChart.
Please let us know if you have any queries.
Thanks,
Muneesh Kumar G.