Quick answer: Mark each affinity-granting choice or conversation as consumed with a persistent flag and skip the gain if the flag is already set, so each grant happens once.
If players can loop one chat to max out a companion's affinity, the gain has no one-time guard. Here is how to make affinity events fire once.
How to fix it
1. Flag consumed grants
Give each affinity grant a unique id and store it in a persistent consumed_affinity set; apply the gain only if the id is absent, then add it.
2. Persist the flags
Save the consumed set so reloading does not reopen the grant, preventing save-scum farming of affinity.
3. Separate repeatable banter
Keep flavor dialogue replayable but gate only the affinity-changing lines, so players can re-hear conversations without exploiting them.
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.
Most of the time the fix is small. Seeing the failure clearly is the part that actually costs you.