System Data taking up 6.20 GB. Help??

[AC Question]

I own a LG Stylo 2 plus from Metro PCS. I recently downloaded a few games (big in size)

The games were:
Modern Combat 5
Asphault 8
N.O.V.A 3
And a few others..

I uninstalled them from the phone. But somehow my storage is full because of System Data


I know there are a few topics on the subject, but i haven't found a solid response. I've searched as haven't found anything

I bought a 32 GB sd card to find out there isn't any way of moving apps of setting it as default storage because of the 6.0 update.

My question is "Is there any way i can clear the system data without factory resetting my phone. Or possibly an alternative to using SD card"

Also there isn't a root available anyways for this phone apparently and the *#9900# function doesnt work to delete the dumpstate files... Sigh.. Please help.

 

[belodion]

The 'system data' may be the OS, which is an essential part of the phone.