For the second time in 5 months, Xfinity has contacted me saying I've used over a TB of data for the month. They said I used 20 GB while my computer was off and I was asleep. I've changed all passwords, etc. and even had an Xfinity rep visit my house and had no idea how that could happen. Xfinity now tells me they're going to bill me for overages. How can this be?
Did you make any changes to your service, besides a bundle change? Did you upgrade your boxes, make a major increase in speed? + speed = more data use
The X1 system uses quite a bit of data.