Appr. 4 yrs. ago I went through 2 Verizon Jetpack Mifi devices that got hacked on the web and not by a local dirt-bag. I live 1/4 mile from anyone and my wifi devices are immediately set to NOT broadcast their SSID as well as changing the default Admin pwd. to something I barely even know.
My 1st device was fine for a month or so, then one day I was blocked from using it because the plan had incurred 4 gig of data usage during the night while I was asleep and my ONLY laptop at the time was off. I use this for work, so I had to pay Verizon for additional data that month.
However, it didn't stop there, the additional was burnt up again within hours and when I worked with the Verizon agents on the phone, they confirmed that the first 4 gig was used up in less than 20 mins. the night before and the 2nd gig purchased was burned up in 1 minute the next day. Keep in mind, that the maximum download speed on those devices would have taken 8 hrs. to download that much data.
So I closed that account & device and bought another ($$$) - the same thing occured within a month. Verizon would not help - only said that regardless of how impossible it would be for the devices I had purchased to burn through gigs of data in that short time period - it none-the-less successfully charged my account's data usage and I was on the hook for it....even though the device was off.
Fast forward to Feb. 2020 and a new device & servce with Verizon and it just happened again - 15 gig plan burnt up and then on the 3/7/20 reset date, 3 gig one night later and then 4 gig 2 nights later, then 1.3 gig the following morning while I had all equipment turned off.
Verizon Mifi's are getting hacked and WE, the consumers are held accountable for the bill, the contract costs, and there have been no considerations given or efforts to remedy this....just the typical - "someone is using your mifi that has your password because other than that, they can't be used/hacked".
Well, read the above and know that this is impossible - these are getting hacked by people with knowledge of the chipsets and software - when they see acct. acitivity - they piggy-back onto it and parasite the data plan at data usage rates that these devices actually cannot perform at. Yet Verizon does nothing to stop it.
No one has the password to this protected device, it is turned off when I'm not working, and all of my devices have auto-update turned off the day I remove them from the box....and I ALWAYS turn auto-update off for every software/service I purchase. Top this off with the data used shown in the Verizon web site. These wifi devices are not capable of 4 gig in 3 minutes....so why does Verizon allow that kind of hit to go onto my accounts each time this happened.....even they acknowledge - "Yeah, that doesn't make sense and is impossible......but there it is"...4 gig in 3 minutes.
Understanding where and how your data is being consumed is crucial to managing your account effectively. Here is a link that will provide you useful tools that will help you monitor and manage your data usage click here https://www.verizonwireless.com/support/tools-for-monitoring-usage/
Here is another link that will provide you more information on data usage FAQs https://www.verizonwireless.com/support/data-usage-faqs/.