Fixed columns in Aurelia project doesn't work

Hi

I have published my Aurelia business project here: https://fysegplannerwebapp.azurewebsites.net/#/projects/CABL2016/employee/28/plan

Y have configured the DataTable in this way:

configureDataTable() {
this.$outSourcingDataTable = $(this.outSourcingDataTable).DataTable({
info: false,
searching: false,
paging: false,
scrollX: true,
fixedColumns: { leftColumns: 4 },
scrollY: "400px",
scrollCollapse: true,
data: this.projectOutSourcingData,
columns: this.columns
});
}

because I want to fix the first 4 columns but does not work. I don't know if is problem of the extension or what

Any idea Please?

Regards