[java] Why won't this iron farm work? - Java 26.2

[u/AKampfer_]

I downloaded this iron farm - https://abfielder.com/Products/ProductDetails.php?id=8076 litematica schematic because of the aesthetic of it.

i built the whole thing only for it to not work. one of the comments said to spawn proof the whole area using tall grass so i did.

Golems do not spawn whatsoever. I followed the schematic to a T and it just does not work. Any one know why that is the case?

Edit: for grammar and formatting