Since last year, have you perhaps changed your IGN? Changing your IGN can reset your statistics and everything you've bought.
Changing IGN's meaning you lose everything. Premium servers use UUID's when joining so if you purchase a rank and change your IGN, your UUID is unique and highlights YOU are YOU, even with a different IGN. We only use the /password feature to identify who is who due to us catering for Cracked players. The password is what helps you identify that you are the person playing on that account, because anyone with a cracked launcher can login and try to join GuildCraft with any IGN.
If this isn't the case, I'll forward this onto an Annihilation staff member/player who may enlighten you furthermore. I don't play Annihilation so frankly my experience and knowledge regarding this sub-server is limited. My apologises.
~ xeph xo