Glitch? – DUM Data usage manager-Track network data usage,Monitor mobile data plan manager Review

It works good but like sometimes it says I’ve used -500mb of data of lets just say 1g and it says I have 1.5 gigabytes left and that I’ve used -50% of my internet? What is that? Otherwise it works great
Review by gsheiruwgeytieowhrh on DUM Data usage manager-Track network data usage,Monitor mobile data plan manager.