tekkit server crashes whenever someone joins

[Unified-Cheese]

i've been running a tekkit server with some friends for about a week, when it lagged for some reason and crashed. when i restarted the server, whenever someone tried to join it would spam this error.

2020-07-13 13:54:13 [SEVERE] [Minecraft-Server] Wrong location! EntityChicken['Chicken'/20616, l='world', x=303.42, y=62.59, z=278.43]
2020-07-13 13:54:13 [INFO] [STDERR] java.lang.Exception: Stack trace
2020-07-13 13:54:13 [INFO] [STDERR]     at java.lang.Thread.dumpStack(Unknown Source)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.chunk.Chunk.func_76612_a(Chunk.java:908)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75823_a(AnvilChunkLoader.java:414)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75822_a(AnvilChunkLoader.java:103)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75815_a(AnvilChunkLoader.java:83)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.gen.ChunkProviderServer.func_73239_e(ChunkProviderServer.java:182)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:118)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.PlayerInstance.<init>(PlayerInstance.java:43)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.PlayerManager.func_72690_a(SourceFile:208)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.PlayerManager.func_72683_a(SourceFile:240)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.ServerConfigurationManager.func_72375_a(ServerConfigurationManager.java:220)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.ServerConfigurationManager.func_72377_c(ServerConfigurationManager.java:268)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.management.ServerConfigurationManager.func_72355_a(ServerConfigurationManager.java:136)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.network.NetLoginHandler.completeConnection(NetLoginHandler.java:201)
2020-07-13 13:54:13 [INFO] [STDERR]     at cpw.mods.fml.common.network.FMLNetworkHandler.handleClientConnection(FMLNetworkHandler.java:167)
2020-07-13 13:54:13 [INFO] [STDERR]     at cpw.mods.fml.common.network.FMLNetworkHandler.onConnectionReceivedFromClient(FMLNetworkHandler.java:121)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.network.NetLoginHandler.func_72529_d(NetLoginHandler.java:185)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.network.NetLoginHandler.func_72532_c(NetLoginHandler.java:71)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.ServerListenThread.func_71766_a(ServerListenThread.java:55)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.dedicated.DedicatedServerListenThread.func_71747_b(SourceFile:29)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:691)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:276)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:587)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:484)
2020-07-13 13:54:13 [INFO] [STDERR]     at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:583)

[JaariAtmc]

This is caused by one or more corrupted chunks and requires Minecraft Region Fixer to fix. Minecraft Region Fixer requires Python 3 to be installed (had to use the windows "app store" in my case for this. Dunno why.)

[Lord Ptolemy]

You're not discussing Tekkit. Moved to Tekkit bug reports.