Strange behavior after sorting by column value

Hi Guys! I have some issue. When page load I have for example 1000 entries. I have some logic in my reportchange event:

this.pivot.on('reportchange', () => {
  this.$nextTick(() => {
    const value = _.cloneDeep(this.pivot.getReport());
    delete value.dataSource;
    this.setFilters({ filter: { reportSetup: { value } }, name: this.filterName });
  });
});

I want to sort by table column value and after that I have for example 2 values instead of 1000, but Flexmonster returns in this.pivot.getReport() all reports without any filtering