Blank customizing theme page

When trying to customize my theme in wordpress I just see a blank screen. I have already deactivated all plugins other than GP-Premium. Still same issue,I also have changed to TwentySeventeen wordpress theme and no problems so I know it's just the generatepress theme. I have also noticed no style.css properties work either.

I've also tried increasing my php memory limit through config.php but that doesn't seem to be working either (or maybe just doing it wrong).