I'm making an incubator block in which you can put eggs which will then result in hatched eggs after some time.
The block entity has 4 slots. Each slot should be able to make it's own progress independently of other slots. When you put an egg in slot 1, the progress of slot 1 should go up over time.

I have the issue where the progress of slots 2 to 4 doesn't go up unless there's eggs in the slots that come before it. For example, slot 2's progress is stuck on 1 if there's no egg in slot 1. As soon as you put an egg in slot 1, the progress of both slots goes up.

Here's the code inside the tick method:
 

public static void tick(Level pLevel, BlockPos pPos, BlockState pState, IncubatorBlockEntity pBlockEntity) {
        if(!pLevel.isClientSide) {
            // Slot 1
            if (hasRecipe(pBlockEntity, 0)) { // 0 references slot 1 which has index 0
                pBlockEntity.slot1Progress++;
                setChanged(pLevel, pPos, pState);
                //System.out.println("Slot 1 progress: " + pBlockEntity.slot1Progress);
                if (pBlockEntity.slot1Progress > pBlockEntity.maxProgress) {
                    craftItem(pBlockEntity, 0); // 0 references slot 1 which has index 0
                    pBlockEntity.resetProgress(0); // 0 references slot 1 which has index 0
                    setChanged(pLevel, pPos, pState);
                }
            } else {
                pBlockEntity.resetProgress(0); // 0 references slot 1 which has index 0
                setChanged(pLevel, pPos, pState);
            }

            // Slot 2
            if (hasRecipe(pBlockEntity, 1)) { // 1 references slot 2 which has index 1
                pBlockEntity.slot2Progress++;
                setChanged(pLevel, pPos, pState);
                //System.out.println("Slot 2 progress: " + pBlockEntity.slot2Progress);
                if (pBlockEntity.slot2Progress > pBlockEntity.maxProgress) {
                    craftItem(pBlockEntity, 1); // 1 references slot 2 which has index 1
                    pBlockEntity.resetProgress(1); // 1 references slot 2 which has index 1
                    setChanged(pLevel, pPos, pState);
                }
            } else {
                pBlockEntity.resetProgress(1); // 1 references slot 2 which has index 1
                setChanged(pLevel, pPos, pState);
            }

		// Slot 3 and 4

 

The constructor with the containerData is as follows:

public IncubatorBlockEntity(BlockPos pWorldPosition, BlockState pBlockState) {
        super(ModBlockEntities.INCUBATOR_BLOCK_ENTITY.get(), pWorldPosition, pBlockState);
        this.data = new ContainerData() {
            @Override
            public int get(int index) {
                return switch (index) {
                    case 0 -> IncubatorBlockEntity.this.slot1Progress;
                    case 1 -> IncubatorBlockEntity.this.slot2Progress;
                    case 2 -> IncubatorBlockEntity.this.slot3Progress;
                    case 3 -> IncubatorBlockEntity.this.slot4Progress;
                    case 4 -> IncubatorBlockEntity.this.maxProgress;
                    default -> 0;
                };
            }

            @Override
            public void set(int index, int value) {
                switch (index) {
                    case 0 -> IncubatorBlockEntity.this.slot1Progress = value;
                    case 1 -> IncubatorBlockEntity.this.slot2Progress = value;
                    case 2 -> IncubatorBlockEntity.this.slot3Progress = value;
                    case 3 -> IncubatorBlockEntity.this.slot4Progress = value;
                    case 4 -> IncubatorBlockEntity.this.maxProgress = value;
                }
            }

            @Override
            public int getCount() {
                return 5;
            }
        };
    }

 

The hasRecipe method simply returns a boolean to tell whether it contains an egg. I'm certain this method doesn't cause issues.

I have determined that the resetProgress method doesn't get called at unintended times either. 

 

So what could be the problem? 

How are you verifying this claim? I assume you're looking at some GUI. If so, can you please provide the code for the menu and screen? I imagine the issue lies there. If not, you need to provide the entire block entity class.