Can somebody help me?

I made this WoodCutter and it was so that when I made a slab, it would give 2 slabs of the corresponding wood, but for some reason it gives 12 dark oak slabs. I don't know where it is in error, can anyone find it for me?

https://www.mediafire.com/file/7ierciymd9b3f6n/woodcutterslabsprocedure.ptpl/file - procedure

https://www.mediafire.com/file/yxxwqderiffma6g/Community_Additions_v0.2.jar/file - mod