Exceptions when clicking on a command sign

[Bloodlex]

Describe the bug I'm getting exceptions when clicking on a sign.

Link to pastebin with this exception: https://pastebin.com/kD4LAVk8 Block configuration: https://pastebin.com/WeSwUT39 Config configuration: https://pastebin.com/4fbL6xcr

To Reproduce Steps to reproduce the behavior:

1. Create a sign
2. Attach a command to signs
3. See error on the console

Expected behavior A clear and concise description of what you expected to happen.

Environment (please complete the following information):

• Linux
• Paper version git-Paper-581 (MC: 1.16.5) (Implementing API version 1.16.5-R0.1-SNAPSHOT)
• 1.16.5

Plugins: Plugins (67): ActionHealth, AdvancedLogger, AdvancedRegionMarket, ArmShopBridge, AsyncWorldEdit, AuthMe, BetterBees, BetterHeads, CommandBlocks, CommandNotifier, CommandPanels, ContainerPassthrough, CraftBook, DeathPenalties, dynmap, Dynmap-WorldGuard, EasyCarts, Epidemic, Essentials, EssentialsChat, GoldenEnchants, GSit, Harbor, HolographicDisplays, Images, InteractiveBooks, JetsAntiAFKPro, Jobs, KeepChunks, LangUtils, Lasso, LastLoginAPI, LeaderHeadsRevamped, LogBlock, LuckPerms, LWC, MobArena, MyCommand, NBTAPI, NexEngine, NoElytra, OpenInv, OreAnnouncer, Orebfuscator, PetMaster, Pingas, PL-Hide-Pro, PlaceholderAPI, Plan, PortalFix*, ProtocolLib, PvPManager, QuickShop, QuickShopDynmap, RegionRaid, SAML, SkinsRestorer, Spartan, SuperVanish, TAB, TitleManager, TreeAssist, Vault, VillagerOptimiser, WorldEdit, WorldGuard, WorldGuardExtraFlags

[Geitenijs]

Works fine for me.. Probably a conflicting plugin?