10 ILCS 5/6-64
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 board of election commissioners 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 such affidavit within thirty days after the mailing of a notice to such elector at the last address from which he has registered, then the registration of such elector shall be cancelled. If either the original or duplicate registration cards, or both, of all registered voters of any city, village or incorporated town or any ward or precinct thereof shall be lost or destroyed, the board of election commissioners shall require a re-registration of electors of such city, ward or precinct.
10 ILCS 5/6-64