If there's no power, there's no usage. It is likely you are seeing the image of the usage before you unplugged it.
The "authorities" will ask for evidence of your claims -- and evidence will also be needed here to prove them. Take pictures and screenshots, with clocks visible.
Without evidence, you won't get much assistance.
I too was a programmer/integrater, since retired for 16 years. If by "unplugged" you mean from the power, I agree with maratsade that there is no way it can be using data, If just the LAN cable is unplugged you'll have to disable the WIFI also. There's all kind of devices that will connect to your WIFI and gobble up your data.
My very first post here was about how I was convinced Hughes was cheating on data usage. After almost a year of tests, the details of which I won't bore you with, I came to the conclusion that if they were cheating it was only about .5 gig a month.
BTW there's a couple of posts pinned to the top here on data usage.
Though it's a bit difficult to tell from your opening statement, are you saying that you use HughesNet for streaming content to your TV? If so, please keep in mind that streaming can use anywhere from 300MB to 3GB or more per hour, depending on the definition of the stream and the streaming service being used.
"I only used at most 4 gb a month doing the same thing I do now but in the three months with HughesNet I have warnings I am running out of data." - Is the "same thing" the streaming mentioned above, or something else?
It's been a while since we last heard from you, so we will close this thread. If you still have concerns, please start a new thread and include a detailed explanation so we can better assist you.