Help with phone storage problem?

A

AC Question

I have a Samsung J320V. It has 16 gigs of memory, 6.34 (a strangely high amount) of which are consumed by System. I run off of Verizon and a Wifi network. Over the past few days, my storage has been consistently "running low." I have tried moving and deleting my photos (mostly screenshots) and uninstalling the apps that I've acquired over the few months since I switched to an Unlimited Data plan. But the system has taken no notice of it, usually keeping a stable display of 180mb and decreasing instead of increasing as it should be. It was at 149mb about 10 minutes ago, I deleted 3 apps (total memory taken up ~300mb) and now it is at 140. Something that I noticed is that it started when I tried to download Italian as an input language for my keyboard (I'm learning it and trying to change my language on websites as part of the whole 'immersion' thing.) The downloading notification didn't go away, even after it was available to add. I restarted my phone and the ability to switch was gone, as was the availability of Italiano as an input language. I clicked download again and the same thing happened, but this time, upon restarting my phone, the "low storage" notification appeared and I was bombarded with these grey bubble notifications every two to five minutes that said "Unable to-" (something something) "space required in bytes:-" (outrageous number) "space available in bytes: 0." and upon switching to a data connection, "Downloading this task is prohibited over this type of connection." It's available currently as a swipe-change, but I don't know how that came to be. Once again, my available storage should definitely be a lot fuller. Any help would be appreciated. Thanks.

ALSO:: My phone is not rooted. It runs Android 6.0.1. If you need any further info about the device, just ask.