Hi Shachr,
Thanks for using Syncfusion products.
Please make sure whether DataSourceID property of the GridGroupingControl is set with DataSource ID.
Also please refer the below sample which illustrates Add/Update and Delete actions on the Database.
http://websamples.syncfusion.com/samples/Grid.Web/5.2.0.25/37815/main.htmPlease let us know if you need more details.
Regards,
Sureshsekaran.