of course you have to archive batches for a material prior to a material.
What you found could be caused by a program error as described in OSS note 1977450 - MM_SPSTOCK: Archiving special stocks
I guess I said it already in earlier replies, before you archive any data make sure that you have the system up-to-date with all OSS notes. Archiving is a very critical activity and not every damage can be repaired and you can loose your data.