If you happen to encounter an issue where a recipe is not enabled but it is unlocked by a technology, most likely you unlocked the technology before a bugfix fixed a missing recipe. The easiest fix to this is re-researching the technology, to do this first you need to un-research it, the following lua command does the job
/c game.player.force.technologies["kovarex-enrichment-process"].researched = false - for kovarex enrichment process specifically.
