Hi Ali,
Thanks for your interest in Syncfusion products.
To avoid splitting of fields, please set the property "ShowNestedPropertiesFields" to false.
this.gridGroupingControl1.ShowNestedPropertiesFields = false;
Please refer to the sample in the following link
http://www.syncfusion.com/downloads/Support/DirectTrac/91626/WindowsFormsApplication17-1011124581.zip
Please let me know if you have any concerns.
Regards,
Mercy.C