Data usage question

Nothing is amiss. Data reporting is not real time. The time on your data usage is not when the data is being used, it is when the data usage is being reported. The actual usage could have occurred many hours and even days before. 

The good news is most of the time data is reported within a few hours, it is pretty rare to take days. The best way to track your data usage is on the phone itself. Just make sure you reset the phone statistics at the beginning of your bill cycle. The phone will have the most up to date usage statistics. When you compare phone to bill, they should be close with the bill generally showing a little less usage than the phone (if the phone usage stats were reset at the right time).

I have a big discrepancy between the cell data usage shown by my tablet and the cell data use shown by AT&T.  The story:

I have a Google Nexus 7 tablet.  I've had it for a couple of years, bought it from Google with an AT&T SIM card.  I don't use much cell data, so I buy (prepaid) 1 GB of data for 90 days.  Calendar time expires, usually, before the 1GB is used up.  

I purchased a plan on March 5 after my last plan expired.  My cell use has been typical since; my tablet showed about 500 mb cellular data used on March 17.  I don't normally sign in on the AT&T buyasession webpage until my plan expires; however, on March 17, I got an e-mail from AT&T announcing that the data limit had been doubled, free of charge, to 2 GB, on my plan.  So I signed in on the buyasession web page to verify the change.

The web page did, indeed, show that the data limit had been doubled.  But it also showed that I had used over 1.3 GB of data.  I called AT&T technical support (very helpful); their tools show that my tablet has used a bit less than 500 mb of data on this plan.  But the data usage shown on the buyasession page remains unchanged at 1.3 GB.  I'm expecting my data plan to terminate when that webpage indicator shows 2 GB.  So, even though my data plan limit doubled, I have about the same amount of data remaining as if it had not.

I habitually switch off cell data when I'm not using it, and switched off app background data on cellular months ago.

I no longer trust AT&T's data use tracking system.  I may buy another plan in June, but maybe not from AT&T.  I like the data plan, the network is  a great, and all the other services I use from AT&T are great.  The tablet came from Google unlocked; it may be time to try another carrier.

I have an Incoming text message contact COD-E28-7898 and I have no idea what this means.  Can anyone explain what this code means?

Thanks. 

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My name is Chet  I am on auto pay I take to a customer service representative to day I am in the hospital I had hip replacement he says he will be able to help me with my phone or my auto pay plane to day until 12/2/2017 he says not to worry about it rest I will call you that day to make my auto pay I will be able and home at that time I hope it will work out I am thankful for the at this time it will will be no problem and delay thanks AT&T

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