Why is my phone suddenly using so many gigs of data

Question

Go to Settings and then to Cellular. There you will see a list of all your apps with the amount of data they have used. Keep in mind the numbers there will not be for the month, but for the phones “current period.” You can see how long this "current period" is by scrolling all the way to the bottom of that page and see when your last period reset was.  For example, if you have an app that says it has used 5.0GB of data, and your date of last reset is March, then sometime in the last 5 months that app has used 5.0GB of data. Now, that could be 1GB a month, or it could be 0.5GB one month and 1.5GB the next month. If you are interested of keeping track of your data on an app by app basis every month I would recommend at the beginning of your billing cycle selecting the "reset statistics" at the bottom of that screen. That way if this happens again you can go to that page and see that app so-and-so used most of the data this month, and maybe be better off in understanding why all your data is gone.  On that same page you have the ability to tell certain apps to never use your cell data. This is done by taping the little ball to the right of the app in this list so that is covers up all the green. You may look through that list and realize that the Notes app used 20MB of data, and ask yourself "Why do I need Notes using my data?" and turn it off.  However, if you do all that and still don’t understand where all the data went that would be the point, personally, when I would try and figure it out with customer service. Let's say for instance you haven’t reset your statistics since March, and your total data usage listed on the phone in the last 5 months is 5GB and your bill says on that same phone says you used 4GB in June and then 3GB in July there may be a serious issue. 

Answer 1

I can't understand why all of a sudden, my data usage has skyrocketed over the last month, when I have not used anything different than I used in previous months. Same goes for text messages. Is it possible for someone to hack into my account??
There has to be some kind of answer