My HTC 516 dual SIM's memory bar was showing a white portion which as per the color codes means... NOTHING!!!

That white part is taking almost half of the memory therefore it is running out of memory in no time.
I just did a hard reset but still I'm getting the same.
What is that white part used for?
Can I solve this so I can use the full available memory?

Screenshot here...
https://www.dropbox.com/s/hvclye8jia...52559.jpg?dl=0

› See More: HTC 516 memory trouble