Goodsync Windows 10 hard drive space gobling

After installing GoodSyc my external backup hard drive started to take up from the 47 GIG of free space that previously had until reached cero space and cannot take-save any data. At first I started erasing unused folders to regain a total to 17 Gigs and I was able to save current work, but next time I turned on the computer the count of space had gone down to cero again. I tried erasing more file a few times with the same result of the count going back to cero free space every time after I turned the computer off.

Hardware and software:

Windows 10 professional
Dell 17", i7, 16 gigs of Ram, 2 terabyte HD
Western Digital Passport Ultra, 2 terabyte external HD