Why is the dataGridView1_SortCompare function not working ?

Question

I have followed the https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.datagridviewsortcompareeventhandler?view=netframework-4.8 document but the dataGridView1_SortCompare column header sort doesn't work ? Although I have declared

this.dataGridView1.SortCompare += new System.Windows.Forms.DataGridViewSortCompareEventHandler(this.dataGridView1_SortCompare);

you see my attached file http://www.mediafire.com/file/pkkrtvd7mdhm94p/1.png