The way pickups were coded is that they destroy themselves when they get picked up, but destroy isn't an instant operation, it will take at the very least one tick to finish destroying itself (and even after that the object will linger until it can be garbage collected usually).

So if you queue multiple orders on the pickup they will all trigger on the pickup before it gets destroyed, triggering the effect multiple times.

Best solution would be for the pickup to track whether it has already been picked up internally and just early-out if it's attempted multiple times.