We have the exact same problem. 6/18. A spike using more than 4 times as usual with less people at home. only 2 of us home watching television and somehow we are to believe we used a huge amount of data? Nothing different done that day (other than no kids on video games as they weren’t here) nothing different the day before or the days since. Just the one day. Cox so far, has been unable to explain but were quick to offer us an upgrade to spend more money on internet service. We had plenty month after month till 6/18. Went over this month due to that one day.