I am using below data table option in Angular application. I want to achieve Row grouping like this example using below code. https://datatables.net/examples/advanced_init/row_grouping.html . But it doesn't do row group. Any help is appreciated. Thank you.

Type Script:
var groupColumn = 1;

this.dtOptions = {
serverSide: true,
processing: true,
dom: 'QBfrtip',
drawCallback: function (settings: any) {
var api = this.api();
var rows = api.rows({ page: 'current' }).nodes();
var last: any = null;
api.column(groupColumn, { page: 'current' })
.data()
.each(function (group: string, i: number) {
if (last !== group) {
$(rows).eq(i).before('' + group + '');
last = group;
}
});
},
ajax: (dataTablesParameters: any, callback: any) => {
that.http
.post(
'https://xtlncifojk.eu07.qoddiapp.com/',
dataTablesParameters, {}
).subscribe(resp => {
that.persons = resp.data;
callback({
recordsTotal: resp.recordsTotal,
recordsFiltered: resp.recordsFiltered,
data: []
});
});
},
columns: [ { data: 'id' }, { data: 'firstName' }, { data: 'lastName' }]
};

HTML: