How to Fix a Unity GameManager Instance Going Null After Unloading an Additive Scene

If your singleton dies whenever you unload one of several additive scenes, the manager is scene-scoped when it needs to be game-scoped. The fix is to give it an owner that outlives every gameplay scene.

How to fix it

1. Host the manager in a boot scene

Create a small bootstrap scene that loads first and contains only the persistent managers. Load gameplay scenes additively on top of it so unloading them never touches the manager object.

2. Promote it with DontDestroyOnLoad

If you must spawn the manager from a gameplay scene, call DontDestroyOnLoad(gameObject) in Awake so it survives the unload of its origin scene.

3. Guard the static accessor

Have Instance log or assert when accessed before initialization, and never cache the reference in Awake of other objects whose load order you do not control.

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.