This assumes you had no ACA/Obamacare coverage for that year, since it was voided you don't enter it at all. if the IRS sent you a notice about a missing 8962, call the number on the notice to explain you had no ACA coverage and that the 1095-A was voided or write them that the 1095-A was cancelled and send them a copy of it to the address specified. if your situation is different, please clarify.