When someone dies in space all their items are dropped and their inventory is cleared because of this if soulbound items are used they will not drop and they will not be in your inventory when respawning. This means that when you get back to your location they won't be there and they will also be lost from your inventory so they are impossible to retrieve.I'm pretty sure this can be easily fixed by simply dropping the items when dying without having your inventory cleared. This would help massively as both slimefun and the slimefun plugin extension tinker tools use soulbound as an enchantment.