Problem/Bug No Fall Damage and Fly In Survival

For some reason i can fly in survival multiverse worlds and will take no fall damage when in survival mode on a survival world. If anyone thinks they might know why plz reply. No permissions are set up apart from plotsquared and HomeSpawnPlus.

PLUGINS:

AdminEssentials
Buycraft
ClearLagg
CombatTagPlus
CompatNoCheatPlus
Essentials
GroupManager
HomeSpawnPlus
Hub
LobbyCompass
MassiveCore
Multiverse (core, inventories and portals)
NoCheatPlus
NoSwar
Orebfuscator3
PerWorldPlugins
PlayerHeads
PlotSquared
ProtocolLib
SilkSpawners
Vault
WorldEdit
aAntiSpam
mcMMO
mcMMO_Horses