The SDU phone number is 877-225-7077. The SDU processes payments for support and maintenance but are not the record keeper of the court case. Any other questions, regarding an extra amount that an employer is garnishing should be directed to Department of Healthcare and Family Services (HFS) at 800-447-4278. HFS (former IDPA) handles all the state cases that our State's Attorney Office takes into court. A printout of payments that the SDU has processed for your case may be obtained at the Circuit Clerk's office located at 540 S. Randall Rd. St. Charles. Copy fees may apply.