Data overage ... here we go again

For the 2nd month in a row, I've gotten the dreaded "You’ve used 75% of your monthly internet data".  Sure enough, in November I went over, but I hadn't used my 'grace month' yet so I wasn't charged.  The 75% message came on 11/15/25, and the 100% message on 11/22/25.  Now in December, the 75% message came on 12/21/25 (yesterday) so I decided to spend some time trying to figure out why my usage has increased suddenly the last 2 months.

I've done a ton of research and this doesn't seem to be a new problem.  And sadly, after jumping through hoops to uncover how to login to my router/gateway again (I have the XBB from Xfinity which I rent), I've determined that I can't find any device usage that way, there's simply no record of it.  The Xfinity app itself just shows overall usage which is useless in trying to determine if you have a rogue device sucking up data.

Our usage has not changed and in fact, we were gone for 12 days during November so I'm having a difficult time believing that our data usage has increased this much in the past two months.  I don't want to get the sales pitch for unlimited data locked in for 5 years!  I've been a very satisfied customer up to this point (5+ years now).

Thank you for reading.