Quick answer: Evaluate unlock rules on the events that can satisfy them (item pickup, level up, station built) and grant the blueprint immediately when a rule passes.
A player gathers the exact item a blueprint needs but the recipe stays greyed out until they restart. Unlock checks only run at startup, not when the prerequisite is actually obtained.
How to fix it
1. Re-check on triggering events
Subscribe unlock evaluation to the events that can satisfy it, such as inventory changes, quest completion, or skill gain. A startup-only check misses in-session unlocks.
2. Persist the unlocked set
Once unlocked, record the blueprint id in saved data so it stays available and you are not re-deriving it from transient conditions every load.
3. Refresh the craft list
After granting an unlock, rebuild or signal the crafting UI so the newly available recipe appears without forcing the player to reopen the menu.
Catching the ones you can't reproduce
The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.
Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.
This is where a tool like Bugnet earns its place. Its SDK captures every Unity error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.
Most of the time the fix is small. Seeing the failure clearly is the part that actually costs you.