So, it is as the title says: my Samsung Galaxy J5 (2016) is filled up. Not with apps, but with "System Memory". The device only has 8 GB of storage, and about ~48%+ of that (3.3 GB) is used by System Memory. Well, apps fill 4 GB, but that is why I have removed about 20% of the system apps (like Google, Hangouts, and many more).
What do I do? How do I get rid of extreme amounts of space used?