Quick answer: Track the next un-awarded threshold and only grant a life when the score crosses it, then advance to the following threshold so each milestone fires exactly once.
Classic arcade games give a 1-up at fixed score points. If you compare score to the milestone as a level rather than an edge, you hand out infinite lives the instant the player passes it.
How to fix it
1. Store the next threshold
Keep a nextLifeScore value (for example 20000). Award a life only when score >= nextLifeScore, then immediately raise nextLifeScore to the next milestone so the same point cannot fire twice.
2. Handle multiple crossings
If a single score gain jumps past several milestones, loop while the score still meets the next threshold so the player gets one life per milestone crossed, not just one total.
3. Cap and persist
Clamp lives to a sane maximum and store nextLifeScore in the save so a reload does not reset it and let the player farm the same milestone again.
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 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.
The errors you never hear about are the ones quietly costing you players. Visibility turns them into a worklist.