Unusually high data usage megathread

https://www.xfinity.com/support/articles/data-usage-what-counts-towards-my-data-plan

My home network usage is show very high activity, yet only 3 devices are connected and none are showing any significant activity.  Also my profiles are zero's when showing 24 hour activity.  My usage meter has been spiking with over 70 GB in one day and I am trying to track down the culprit.  But if usage monitoring does not work correctly, how am I supposed to do it?

I have done a hard modem reset by unplugging it.  changed my wifi passwords and made sure all laptops are off.

What am I missing?

I have been a Comcast customer for many years and never ever been close to a limit. Over 2019 I used an average of 220GB a month. December rolls around and I get an email that I am over the 1TB limit. The only change was i added Disney plus. I have since removed DIsney plus and still my data rate is off the charts. I purchased a new modem and setup an entire new network. Still my data rate is off the charts. Customer service has been NO help at all. I have scanned everything and replaced equipment at MY cost and still no relief.

I NEED HELP FROM MY PROVIDER XFINITY (COMCAST)

@Annapolismike

 
I think this forum is going about it the wrong way.  You said hard reset of modem.  That's cool, but what modem specifically?  Unplug won't do factory defaults and you might want to do that too if it's been jacked.  Also, factory defaults might not be what you're looking for here.  Sometimes, there are really insecure settings -- you know, to make it easy for people.  They're not good usually.
 
Wifi passwords.  Sure.  Thats if your neighbor is dogging you which is unlikely with wpa2 unless you're using the SSID for a password, what about the default admin password for the router itself?  Change that too.  Also, while you're in there:
 
Disable ICMP
Disable UPnP
Disable Remote Access  to the modem of any kind (ssh, web, hopefully it has no telnet option)
Do Not port forward, unless you have that covered by "other means" with a real firewall. If you find port forwards or port trigging -- you've been pawnd already (world accessible).  Reset again.  Change the default modem password (not just the wifi).
 
Disable any kind of file sharing on the modem (Netgear ReadyShare specifically -- advanced -> setup).

Make sure the firewall is on.  If it's got a portscan block option, turn that on too.

Some modems have remote exploits.  Model would help.  What is it?  What firmware does it say.  Maybe there's something else to look at.  Netgear has decided NOT to fix some of them.  Government CERT warnings say not to use them at all.
 
70G is nuts on wifi in 24 hours unless you're trying to do that.  If you change the settings above, see what it is in the next 24 hours.  Other devices on your network can be exploited too.  Try the above and see if it helps.  Go from there.

Everyone assumes that the data is suddenly wrong.  What if it is actually right now and was incorrect before?  My router says I have used 450GB and Comcast is reporting 800GB.  This could be correct if my router isn't counting the Netflix app used through the X1 Box.  I guess I could test this by turning off wifi and seeing if the Netflix app still works.  But I'm too lazy.  I want Comcast to tell me what's going on.  That seems like a lot of data, but I would expect it to be a lot higher since it's a 65 inch 4K TV.  If the router is only reporting streaming to a phone or ipad then it makes sense.

Followup:  After looking at router data, it breaks it down further.  Of the 115GB Netflix usage, 87GB is used on the ipad (my daughter is a Friendsaholic). The rest are on other phones.  My wife and I use the app within Comcast.  All that data going to the big screen is not being counted by the router.  So the only question I have is, Does that app usage count against the monthly limit? I assume it probably is counted on the chart so the answer is Yes.  I live in a state with no cap, so I am good.  But I would bet that those numbers that you are seeing are legit.

This is trually puzzling my household averages 450 to 575 gigs a month of data witch is likley high to some but we do alot of streaming. Usage has been constent for yrs at that level, but suddenly this month were already  over 1024 at 1/21/2020. according to the e-mail I was sent. (1054)

All our devices added together show a grand total of around 600 combined of 4 devices. now thats means they are saying I'm using double data how is that making sence. I think they have a bug in there system and are looking for a lawsuit. 

25 yrs with xfinity(comcast) around 20 with xfinity internet. I think they have something trualy wrong with there wifi tracking and need to own up to there internal issue. Causemy devices haven't changed in over 5 yrs then suddenly this month I have double data usage with  zero changes in usage.

Yeah right!

I'll be making some phone calls today but based on thread have a feeling that will net me a pointed finger at everything but comcast,

A. comcasting having no idea whats going on

B. comcast taking zero responcability for there system errors.

C. wasting my time and them charging falsely for services.

Had another thought as well perhapse they are adding 2 households together. Readings not off the the devices in ones home but the actual cable dome out in the front yard. 2 house holds on the same hub perhapse there systems are combining the readings to one household or dupping them to both households. Will check with my neighbore if they got hit with crazy usage also.

Either way comcast needs to fix there issues.

I too have been fighting Comcast for months about data usage suddenly doubling and then staying high. This started to become a consistent issue in early 2019 where I'd routinely go over my data cap by about 100gb after being stable around 700gb prior to that. We only use the internet in the afternoons and on weekends. One person in the house is out of town 2 out of the 4 weeks every month. My router backed this up continually ending up around that same amount in the data usage meter at the end of each month, and did not climb further with the comcast meter. It had stayed roughly at that level regardless of the Comcast readings until my hand was forced to switch to you rhardware due to multiple techs/reps stating they can't help unless I use the xfi stuff. This was done on Nov 29.

As you can see after July with the exception of October our overage amount is signifant, becoming astronimical in November.

The problem could still not be diagnosed, but the overage amounts still weren't enough to justify moving to unlimited until we arrived in November where the household exceeded the limit by 661 gb. Again no usage changed to warrant such a massive increase.  After reveiwing the bill in response I called one of your reps on Dec 22 to say I can't keep getting hit with these charges and I'm done being surprised by bills—lets just add the unlimited if we can take care of my $140 overages from November showing . The rep stated that seeing as I was adding this in December it should apply to my open bill for the previous month of November as those charges should show on my current bill, and no future overage charges will apply. He noted a credit should be applied to balance out those charges.

I've spoken to 3 people in the last 3 days and received zero help on the charges that I believe are the result of ongoing incorrect data usage. Oner person forwarded me to a full invoice with your data team, one stated it was after hours but he gave me his word he would resolve this issue for me by getting me the refund and returning my call the next day which he never did, and today I was told that this kind of retroactive application of a service is not permitted and the best they could do is refund me $90 of the $140 which I've tentatively accepted until a better solution can be offered.

So to summarize we've had an ongoing data issue with massive spikes since the beginning of last year with no change to usage. I've called your security team several times and they refused to help unless I moved to your hardware. I made the switch to your hardware at the request of your security team in late November and still a diagnosis could not be made. I then requested a change to unlimited to avoid surprises and was told by your rep my $140 fee should go away with this change. I have followed up with 3 reps, 1 of which never returned my call even though they stated this would be resolved, one sent me to a dead end, and one was compeltely unhelpful stating that I must have been in the wrong this entire time. It does not make sense we're using 50gb+/- of data a day when usage is limited to evenings.

@ComcastTeds please help! Ideally I'd like my massive data issues diagnosed and resolved, but at at a minimum I'd like for your company to maintain its word and remove these charges.

https://imgur.com/a/JMwE1AD

I have had xfinity services since 2016 and have been a loyal customer. In October 2019 I started receiving the following emails from xfinity "You've used 100% of your data plan this month". At first thought I didn't think anything of it. November same email from xfinity "You've used 100% of your data plan this month". Finally, in December I realized something was wrong. On December 5th I called into internet support and then was transferred to internet security. I was told maybe the following issues could be causing the data overage; data leak, the network could have been compromised, and possibly the modem. They suggested to replace the modem and create new network name and password. I scheduled a technician visit to replace the modem and create a new network name. I was also told they would had $50 for unlimited data until we could resolve the issue. We are now in January and continue to skyrocket with our data usage. I have called numerous time only to be told "you have unlimited data, there's nothing to worry about". Today I decided to call once again to try and look into the issue further. Upon talking with internet security and level 2 security assurance I stumbled on the following article: https://arstechnica.com/information-technology/2019/10/comcast-incorrectly-charged-2000-customers-for-exceeding-data-cap/
I can't say this is the same issue other xFinity customers were having but it does seem pretty identical. Our data the last previous years has been consistent. Using the xFi app looking at each device individually the data doesn't add up. Something is wrong.

I have spent hours upon hours trying to get to the bottom of this issue. I am reaching out for help. I am completely frustrated and beyond disappointed! I am at the end of the road without any solutions.

The last representatives information is listed below:
Ticket #NA250408400
Level 2 Security Assurance
ID #101465

I'm sorry to hear that. Xfinity hasn't been able to pinpoint what device/devices is using up all my data. I have double my regular data usage with no explantion. I now have emailed corporate. Let's see if I can get some resolution.