When i attempted to water-log a block , it has an "air" skin wrapped around the horizontal faces.

 

	public class WaterShape extends YabmBlock implements SimpleWaterloggedBlock {

		
		public static final BooleanProperty WATERLOGGED = BlockStateProperties.WATERLOGGED;
		

		public WaterShape(Properties properties) {
			super(properties);
			 this.registerDefaultState(this.stateDefinition.any().setValue(WATERLOGGED, Boolean.valueOf(false)));
		  }

		@Override
		protected void createBlockStateDefinition(StateDefinition.Builder<Block, BlockState> p_48725_) {
			p_48725_.add(WATERLOGGED);
		 }
		
		  @Override
		  @Nullable
		   public BlockState getStateForPlacement(BlockPlaceContext context) {
			  FluidState fluidstate = context.getLevel().getFluidState(context.getClickedPos());

			  boolean flag = fluidstate.getType() == Fluids.WATER;
		         //return super.getStateForPlacement(context).with(WATERLOGGED, Boolean.valueOf(flag)).with(FACING, context.getPlacementHorizontalFacing());
		         return super.getStateForPlacement(context).setValue(WATERLOGGED, Boolean.valueOf(flag));
	      }


		   public FluidState getFluidState(BlockState p_56131_) {
			      return p_56131_.getValue(WATERLOGGED) ? Fluids.WATER.getSource(false) : super.getFluidState(p_56131_);
			   }

		   
		      
	}

 

 

 

This is how I fixed it not sure this is the correct way, but it works

  boolean flag = fluidstate.getType() != Fluids.EMPTY;  boolean flag = fluidstate.getType() != Fluids.EMPTY;

Added this method

	  @Override  
	  public boolean canPlaceLiquid(BlockGetter p_54325_, BlockPos p_54326_, BlockState p_54327_, Fluid p_54328_) {
		  return false;
	  }