Mods: RPG Mod (v. 0.6.13)

java.lang.NullPointerException: Cannot invoke "rpgclasses.data.EquippedActiveSkill.run(necesse.entity.mobs.PlayerMob)" because "equippedActiveSkill" is null
at rpgclasses.buffs.CastingBuff.onRemoved(CastingBuff.java:43)
at necesse.entity.mobs.buffs.BuffManager.clientTick(BuffManager.java:228)
at necesse.entity.mobs.Mob.clientTick(Mob.java:630)
at necesse.entity.mobs.AttackAnimMob.clientTick(AttackAnimMob.java:21)
at necesse.entity.mobs.itemAttacker.ItemAttackerMob.clientTick(ItemAttackerMob.java:128)
at necesse.entity.mobs.PlayerMob.clientTick(PlayerMob.java:710)
at necesse.engine.network.client.ClientClient.tick(ClientClient.java:82)
at necesse.engine.network.client.Client.tick(Client.java:306)
at necesse.engine.platforms.steam.network.client.SteamClient.tick(SteamClient.java:81)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordPerformance(PerformanceTimerManager.java:105)
at necesse.engine.gameLoop.tickManager.Performance.record(Performance.java:10)
at necesse.engine.state.MainGame.frameTick(MainGame.java:449)
at necesse.engine.gameLoop.ClientGameLoop.lambda$update$5(ClientGameLoop.java:78)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordConstantPerformance(PerformanceTimerManager.java:113)
at necesse.engine.gameLoop.tickManager.Performance.recordConstant(Performance.java:16)
at necesse.engine.gameLoop.ClientGameLoop.update(ClientGameLoop.java:76)
at necesse.engine.gameLoop.tickManager.TickManager.tickLogic(TickManager.java:98)
at necesse.engine.gameLoop.GameLoop.runMainGameLoop(GameLoop.java:24)
at necesse.engine.loading.ClientLoader.startGame(ClientLoader.java:366)
at necesse.StartPlatformClient.start(StartPlatformClient.java:12)
at StartSteamClient.main(StartSteamClient.java:6)

Plz help me...