http://pastebin.com/tSLbHYm0

It's caused by potions or bottles with different name or lore i believe, i thought it was the plugin brewery but I edited lore and name of a water bottle and the error showed up

Unfortunately this is because you're running Spigot 1.8. You'll need to use an older build of HyperConomy or upgrade to 1.9 to get rid of this error. I had to use some new methods in 1.9 to support new features.