Total data usage 491.3TB

Have you been downloading a number of games/movies lately?

Have you disconnected it from your network to see if that is the device that is causing it?

Do you have a number of users that could be streaming everything (including having videos auto-play in some phone apps/websites)?

Is your network secured, as in could someone have figured out how to get on your network and started downloading movies/games? (Had this happen with a stolen mi-fi unit and caught it just before it went over the data plan of the
month).

If you can supply some additional info, maybe we can help figure out what's going on.

Data usage is going to vary from user to user, depending on the individuals use.

While data usage for initial setup would be minimal, the downloading of games can eat up data rather quickly. With many games being in the 50 GB range, some can be as high as 100+ GB each. Apps, web browsing, TV/Movie streaming etc. will all contribute to
total usage... it doesn't take long to add up.

I recently was added to the Self Service refund program via a Xbox Live message. So I went to refund my first game through my Microsoft Order History page but it's giving me the usage data error. This is for Dark Souls Remastered. I tried opening the game
to see if opening the game would register usage data and fix the issue but it didn't fix it. It was for about a min total. Any idea how to fix this issue?

Hey there! I did a little searching and I can't find the official answer (if there is one) but I'm seeing most other players estimating it between .5-1 gig an hour. You might try clocking the speed on your current network to see what it really looks like
more accurately. You can also try in the game-specific forums over here and see if any players know for sure! Call of Duty: Black Ops 2 -
Forum.

Hope this helps!

I have a a little less Gigs then you but I play quite a lot and I don't usually go over the limit don't even get close to going over.