I am currently at early game, so I use Tom's Storage Mod for my storage system and created a quarry in mining dim. I forced to load chunks with FTB Utilities, but when I'm not in overworld after about half minute storage system stops accepting items. All storage system is in one chunk.

Can also confirm that .21 has loading issues again.

Having the same issue. I have some machines (rs autocrafting, bigger reactor) in the Compact Machines dimension and for some reason they unload when you leave the dimension even when force loaded.

On 0.3.15

Edit: Also getting this error, not sure if it's related, when I go to the Compact Machines dimension. I believe it's caused by my refined storage system unloading in the overworld when I'm trying to access it via a receiver.
[18:23:23] [Server thread/ERROR] [minecraft/PacketUtils]: Failed to handle packet net.minecraft.network.protocol.game.ServerboundUseItemOnPacket@77a66336, suppressing error java.lang.NullPointerException: Cannot invoke "com.refinedmods.refinedstorage.api.network.INetwork.getCraftingManager()" because the return value of "com.refinedmods.refinedstorage.apiimpl.network.node.CrafterManagerNetworkNode.getNetwork()" is null at com.refinedmods.refinedstorage.container.factory.CrafterManagerMenuProvider.writeToBuffer(CrafterManagerMenuProvider.java:31) ~[refinedstorage-1.10.2.jar%23222!/:1.10.2] {re:classloading} at com.refinedmods.refinedstorage.block.CrafterManagerBlock.lambda$use$0(CrafterManagerBlock.java:47) ~[refinedstorage-1.10.2.jar%23222!/:1.10.2] {re:classloading} at net.minecraftforge.network.NetworkHooks.openGui(NetworkHooks.java:189) ~[forge-1.18.2-40.1.0-universal.jar%23282!/:?] {re:classloading} at com.refinedmods.refinedstorage.block.CrafterManagerBlock.lambda$use$1(CrafterManagerBlock.java:44) ~[refinedstorage-1.10.2.jar%23222!/:1.10.2] {re:classloading} at com.refinedmods.refinedstorage.util.NetworkUtils.attempt(NetworkUtils.java:66) ~[refinedstorage-1.10.2.jar%23222!/:1.10.2] {re:classloading} at com.refinedmods.refinedstorage.block.CrafterManagerBlock.m_6227_(CrafterManagerBlock.java:44) ~[refinedstorage-1.10.2.jar%23222!/:1.10.2] {re:classloading} at net.minecraft.world.level.block.state.BlockBehaviour$BlockStateBase.m_60664_(BlockBehaviour.java:697) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,xf:fml:libx:random_tick_block,re:classloading,pl:accesstransformer:B,xf:fml:libx:random_tick_block,pl:mixin:APP:ferritecore.blockstatecache.mixin.json:BlockStateBaseMixin,pl:mixin:APP:immersiveengineering.mixins.json:coremods.AbstractBlockStateMixin,pl:mixin:APP:kubejs-common.mixins.json:BlockStateBaseMixin,pl:mixin:APP:byg.mixins.json:common.block.MixinBlockBehaviourBlockStateBase,pl:mixin:A} at net.minecraft.server.level.ServerPlayerGameMode.m_7179_(ServerPlayerGameMode.java:344) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,xf:fml:libx:interact,re:computing_frames,pl:accesstransformer:B,xf:fml:libx:interact,re:classloading,pl:accesstransformer:B,xf:fml:libx:interact,pl:mixin:APP:mixins.artifacts.json:item.diggingclaws.ServerPlayerGameModeMixin,pl:mixin:APP:kubejs-common.mixins.json:ServerPlayerGameModeMixin,pl:mixin:A} at net.minecraft.server.network.ServerGamePacketListenerImpl.m_6371_(ServerGamePacketListenerImpl.java:987) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mixins.artifacts.json:item.umbrella.ServerGamePacketListenerImplMixin,pl:mixin:APP:expandability.mixins.json:swimming.server.ServerGamePacketListenerImplMixin,pl:mixin:APP:immersiveengineering.mixins.json:accessors.ServerPlayNetHandlerAccess,pl:mixin:APP:tombstone.mixins.json:ServerPacketMixin,pl:mixin:A} at net.minecraft.network.protocol.game.ServerboundUseItemOnPacket.m_5797_(ServerboundUseItemOnPacket.java:30) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:classloading} at net.minecraft.network.protocol.game.ServerboundUseItemOnPacket.m_5797_(ServerboundUseItemOnPacket.java:8) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:classloading} at net.minecraft.network.protocol.PacketUtils.m_131356_(PacketUtils.java:22) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:classloading} at net.minecraft.server.TickTask.run(TickTask.java:18) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:classloading,re:mixin} at net.minecraft.util.thread.BlockableEventLoop.m_6367_(BlockableEventLoop.java:157) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:computing_frames,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B} at net.minecraft.util.thread.ReentrantBlockableEventLoop.m_6367_(ReentrantBlockableEventLoop.java:23) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,re:computing_frames,re:classloading} at net.minecraft.server.MinecraftServer.m_6367_(MinecraftServer.java:799) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.server.MinecraftServer.m_6367_(MinecraftServer.java:164) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.util.thread.BlockableEventLoop.m_7245_(BlockableEventLoop.java:131) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:computing_frames,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B} at net.minecraft.server.MinecraftServer.m_129961_(MinecraftServer.java:782) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.server.MinecraftServer.m_7245_(MinecraftServer.java:776) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.util.thread.BlockableEventLoop.m_18701_(BlockableEventLoop.java:140) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:computing_frames,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B} at net.minecraft.server.MinecraftServer.m_130012_(MinecraftServer.java:762) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.server.MinecraftServer.m_130011_(MinecraftServer.java:689) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at net.minecraft.server.MinecraftServer.m_177918_(MinecraftServer.java:261) ~[server-1.18.2-20220404.173914-srg.jar%23278!/:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:elementalcraft.mixins.json:MixinMinecraftServer,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:APP:byg.mixins.json:access.MinecraftServerAccess,pl:mixin:APP:byg.mixins.json:server.MixinMinecraftServer,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:A} at java.lang.Thread.run(Thread.java:833) [?:?] {re:mixin}

I can confirm this as well, it seems fairly random but in single-player worlds any chunks that were force loaded when you quit won't be loaded when it starts again (using FTB Chunks loading)

I found out that you can use command /forceload add, then it works, but FTB Utilities still not working

I am also having this issue in 0.3.18, my compact machine will not stay loaded. I tried using the ftb chunks setting, the little logistics chunk loader items and the more minecarts chunk loader but none of them seem to be able to keep the interior of my machine loaded.

Also having this issue in 0.3.18, in mining dimension with ftb utilities and mekanism fission reactor.

Let me know how its working on the new 0.3.19 update. Chunks was updated to fix this hopefully.

0.3.21 has this same issue, atleast with the overworld & compactmachines dimension that I've tested.