So I posted a thread where it said that this plugin clears inventories, and yes, it is true. I don't really understand why, its just a rankup plugin, but I have uninstalled and reinstalled and when I uninstalled the bug wasn't there anymore, so im 100% sure its your plugin, it gets you back from the position and inventory you had before installing the plugin, I have tested twice, and it happens again. Please help me.
Plugin list:
AuthMe
Block
Buycraft
Clearlag
CombatLog
Essentials, core, chat and spawn
Info-Board
MineResetLite
Multiverse-Core
PermissionsEx
PlotMe
PrisonRankup
VanishNoPacket
Vault
WorldEdit
WorldGuard

No errors in console/logs.