DSI PolyEvolver bottom octave not responding

Hi, I had a few dirty contacts that were causing notes not to work on my PEK so I took it apart and cleaned them this afternoon. All of those notes are now responding again but the lowest octave is now not responding at all - does anyone know what might cause this with a (presuming) Fatar tp/9s keybed? Never had this issue before…

So it turns out it was a simple error - I put the silicone key contact strip on the wrong way. Easy fix!