Top layer gaps

I'm having problems with the top layers not filling in. I've tried adding more top and outer layers and I even tried adding more infill thinking because there was very little there wasnt enough support to fill in the top parts.

I'm also getting bumps/ lines where the layer start points are and when I print in Cura I don't get that problem. Is there a way to get rid of it in Simplify other then making a seam line or scattering the start points around? I attached a photo to get a better idea what I mean.


(I'm printing on an Ender 3 with PLA, sliced with Simplify3D)