Can You Help Me With This Error ? I Was Making A Grid View Label Delete Buttonlink Then It Always Says Overload !!

protected void grdList_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName.Equals("Insert"))
        {
            TextBox txtCode = (TextBox)grdList.FooterRow.FindControl("txtNewCode");
            TextBox txtDescription = (TextBox)grdList.FooterRow.FindControl("txtNewDescription");
            bool result = ProductManager.SaveProductGroup(txtSearchCode.Text,txtSearchGroup.Text, txtSearchDescription.Text,"A");
            FillGrid();
        }
        else if (e.CommandName == "Delete")
        {
            
            string ProductGroup = Convert.ToString(e.CommandArgument);
             
            bool result = ProductManager.DeleteProductGroup(ProductGroup);
            //MY ERROR IS THIS IT ALWAYS SAYS " Error 1 No overload for method 'DeleteProductGroup' takes 1 arguments	D:\Projects\POSInventory\ProductGroup.aspx.cs	46 27 D:\Projects\POSInventory\"

            FillGrid();

            
        }
    }