I was playing today doing some things with redstone, the hopper wasn't taking objects.

I restarted the server, and suddenly when I logged, the server instantly crashed.

---- Minecraft Crash Report -------- Minecraft Crash Report ----// But it works on my machine.
Time: 21/02/19 22:40Description: Ticking entity
java.lang.NullPointerException: Ticking entity at ahw.a(SourceFile:1049) at ahw.dD(SourceFile:1038) at aic.dD(SourceFile:35) at ahw.h(SourceFile:289) at anw.h(SourceFile:573) at aod.h(SourceFile:83) at uv.a(SourceFile:565) at bdf.a(SourceFile:683) at uv.a(SourceFile:368) at net.minecraft.server.MinecraftServer.b(SourceFile:837) at tw.b(SourceFile:342) at net.minecraft.server.MinecraftServer.a(SourceFile:776) at net.minecraft.server.MinecraftServer.run(SourceFile:634) at java.lang.Thread.run(Unknown Source)

A detailed walkthrough of the error, its code path and all known details is as follows:---------------------------------------------------------------------------------------
– Head --Thread: Server threadStacktrace: at ahw.a(SourceFile:1049) at ahw.dD(SourceFile:1038) at aic.dD(SourceFile:35) at ahw.h(SourceFile:289) at anw.h(SourceFile:573) at aod.h(SourceFile:83) at uv.a(SourceFile:565)
– Entity being ticked --Details: Entity Type: minecraft:trader_llama (aod) Entity ID: 301 Entity Name: Trader Llama Entity's Exact location: -817.51, 80.00, 535.54 Entity's Block location: World: (-818,80,535), Chunk: (at 14,5,7 in -52,33; contains blocks -832,0,528 to -817,255,543), Region: (-2,1; contains chunks -64,32 to -33,63, blocks -1024,0,512 to -513,255,1023) Entity's Momentum: 0.00, -0.08, 0.00 Entity's Passengers: [] Entity's Vehicle: ~_ERROR~ NullPointerException: nullStacktrace: at bdf.a(SourceFile:683) at uv.a(SourceFile:368)
– Affected level --Details: Level name: world All players: 1 total; [uw['Alwee'/102, l='world', x=-938.85, y=80.00, z=580.43]] Chunk stats: ServerChunkCache: 3706 Level seed: -5148218317190742635 Level generator: ID 00 - default, ver 1. Features enabled: true Level generator options: {} Level spawn location: World: (128,66,144), Chunk: (at 0,4,0 in 8,9; contains blocks 128,0,144 to 143,255,159), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511) Level time: 1037379 game time, 107206 day time Level dimension: 0 Level storage version: 0x04ABD - Anvil Level weather: Rain time: 1884 (now: true), thunder time: 170386 (now: false) Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: falseStacktrace: at net.minecraft.server.MinecraftServer.b(SourceFile:837) at tw.b(SourceFile:342) at net.minecraft.server.MinecraftServer.a(SourceFile:776) at net.minecraft.server.MinecraftServer.run(SourceFile:634) at java.lang.Thread.run(Unknown Source)
– System Details --Details: Minecraft Version: 19w08b Operating System: Windows 10 (amd64) version 10.0 Java Version: 1.8.0_201, Oracle Corporation Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation Memory: 3210499984 bytes (3061 MB) / 3695706112 bytes (3524 MB) up to 3817865216 bytes (3641 MB) JVM Flags: 3 total; -Xms2048M -Xmx4G -Xmx4096M Player Count: 1 / 20; [uw['Alwee'/102, l='world', x=-938.85, y=80.00, z=580.43]] Data Packs: vanilla Is Modded: Unknown (can't tell) Type: Dedicated Server (map_server.txt)