Split Surface not working

Heey, I'm having an issue with split surface. I have all the curves projected on the srf I want to split and the srf itself but the split doesn't occur. My aim is to create smaller "cells" (grey) in the platforms (light blue) (as  shown in the picture). Furthermore I would strictly need to maintain the data structure since then I need to use each cell differently depending on its order, and on which platform it is.

Does anyone know why this is happening??

Thanks in advance!