What causes level-up granting rewards for the old level?

The reward lookup ran before the level counter was incremented, so it keyed the reward table on the level the player was leaving instead of the one they reached.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix Level-Up Granting Rewards for the Old Level

Quick answer: Increment the level first, then look up rewards by the new level, and loop the grant across every level crossed when a big XP gain skips multiple levels.

When dinging to level 10 gives you the level 9 reward, your code is reading rewards off the stale level value. Incrementing before the lookup, and iterating over every level crossed, fixes it. Here is how.

How to fix it

1. Increment, then look up

Apply the level increase to the stored level first, then call reward_for_level(new_level). Reading the table before the increment grants the level you just left.

2. Loop over skipped levels

A single large XP award can cross several levels; loop from old_level + 1 to new_level and grant each level's reward, not just the final one.

3. Guard against double grants

Track the highest level already rewarded so a recomputation or reload does not re-grant a level the player already received.

4. Emit one event per level

Fire a level-up signal per crossed level with the correct level number so UI popups and reward lists match what was actually granted.

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 Godot 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.

Reproduce it once with full context and the fix writes itself. The hunt is the expensive part.