merging blocks end up overlapping | Suphi Kaner | Page 1

im working on a script to merge blocks that are the same colour, they currently merge in invalid spots though, any ideas on how i could implement a check for this in my --y code?
relevant snippet:

    -- x
    for x = 2, GRIDSIZE do
        for z = 1, GRIDSIZE do
            for y, size in pairs(sizes[x][z]) do

            if sizes[x - 1][z][y] == nil then continue end
            if size.X ~= sizes[x - 1][z][y].X then continue end
            if blocks[x][z][y].Colour ~= blocks[x - 1][z][y].Colour then continue end

            sizes[x][z][y].X += sizes[x-1][z][y].X
            sizes[x-1][z][y] = nil
            end
        end
    end

    -- z
    for x = 1, GRIDSIZE do
        for z = 2, GRIDSIZE do
            for y, size in pairs(sizes[x][z]) do
            
            if sizes[x][z-1][y] == nil then continue end
            if size.Z ~= sizes[x][z-1][y].Z then continue end
            if blocks[x][z].Colour ~= blocks[x][z - 1][y].Colour then continue end

            sizes[x][z][y].Z += sizes[x][z - 1][y].Z
            sizes[x][z - 1][y] =  nil
            end
        end
    end
    
    
-- y
for x = 1, GRIDSIZE do
    for z = 1, GRIDSIZE do
        for y, size in pairs(sizes[x][z]) do
            if sizes[x][z][y-1] == nil then continue end
            if size.Y ~= sizes[x][z][y-1].Y then continue end
            if blocks[x][z][y].Colour ~= blocks[x][z][y-1].Colour then continue end

                sizes[x][z][y].Y = sizes[x][z][y].Y + sizes[x][z][y-1].Y
                sizes[x][z][y-1] = nil
                end
            end
        end

representation of whats happening:

#merging blocks end up overlapping