Rendering a sphere using Light Up

Hello, this is my first ever post so any help would be much appreciated! I’ve drawn a lightbulb shape as part of a model, but it is rendering (Lightup Pro) with sections of the sphere in black. I’m needing a smooth rounded shape, but the result is very low fi looking even though the rest of the model looks great

Here’s an image that will hopefully explain what’s going on. Any advice folks? Thanks, N

Perhaps the light bulb model has some reversed faces?