SPRINGFIELD — The state is no longer charging interest on late child support payments that are made through the Department of Healthcare and Family Services unless it’s ordered by a court, and all of the outstanding interest charges that those parents owed have been zeroed out.A spokesman for the agency said in an email that the total accrued interest penalties that were eliminated amounted to just over $2.7 billion.DHFS made that announcement Monday, saying those interest charges fell disproportionately on low-income …