Hi Deepak,
Thanks for using Syncfusion Products.
In GridGroupingControl, the header sorting can be cancelled by handling the "TableControlQueryAllowSortColumn" event with the following code.
e.AllowSort = false;
Here is the sample for your reference.
http://www.syncfusion.com/uploads/redirect.aspx?&team=support&file=HeaderSorting-649799832.zipPlease let us know if you have any other concerns.
Regards,
Yuvaraja V.