When I'm building with baritone it keeps pausing the build and telling me I'm missing 4x null

Final checklist

• I know how to properly use check boxes
• I have not used any OwO's or UwU's in this issue.

fix your schematic so it doesn't contain nulls

No, there's really a bug that causes null to end up in the error message even with a sane schematic.
Canceling and restarting the builder "fixes" it, until whatever causes this happens again.

This is possibly a duplicate of #3428 (which is probably a duplicate as well but it is so detailed I'd rather close the older ones instead)