10 ILCS 5/4-19

If either the original or duplicate registration card, or both, of any elector shall be lost, destroyed or mutilated in whole or in part, the county clerk shall prepare two new registration cards, an original and a duplicate and shall require the execution of a new registration affidavit by such elector, and if any such elector shall refuse to execute the affidavit within thirty days after the mailing of a notice to him at the last address from which he has registered, then his registration shall be cancelled.