To put simply, I downed Nien and received a helm which after upgrading, was a better item than what I currently have. So, after evolving it, I spent 20 or so diamonds for the mats needed to upgrade to the next tier. Do another Nien fight for more mats, come back and find the helm is now gone? What gives? Can someone either reimburse me the diamonds or return the helm (which I'd rather have)?