Problem/Bug Server Randomly Becomes Unjoinable

Sometimes my friends server because unjoinable the players on it are still on but if you try to join you cant

Plugins: CoreProtect, CmdSpy, PlaceholderAPI, VoidWorld, AutoSmelt, ClearLag, PlayTime, BannerBoard, ProtocolLib, Multiverse-Core, NoCheatPlus, PrisonShops, eZProtector, AntiDrop, FastAsyncWorldEdit, DropToInventory, VoxelSniper, DeluxeMenus, PermissionsEx, Vault, StaffPlus, AntiJigsaw, WorldEdit, Essentials, Rankup, SimpleRename, HolographicDisplays, WorldGuard, Citizens, EssentialsChat, MineResetLite, EssentialsSpawn, CratesPlus, EnchantsPlus, CitizensCMD, Click2Enchant

Console Log: https://pastebin.com/0TNUTUJf