Canning - Re-Processing Unsealed Jars
If a lid fails to seal on a jar, remove the lid and check the jar - sealing surface for tiny niches. If necessary, change the jar, add a new, properly prepared lid, and reprocess within 24 hours using the same processing time.
Headspace in unsealed jars may be adjusted to 1 ½ inches and jars could be frozen instead of reprocessed. Foods in single unsealed jars could be stored in the refrigerator and eaten within several days.