Data Usage?

Data is not reported when used.  Read your bill (see below)

Your phone is an independant meter of your data use.  Look at what the phone says you used for the bill cycle.  In settings, data usage.  iPhones will not have data by bill cycle.  

99 mb is less than 1/10 of a gig.  At that rate per day a 3 gig plan would be used up in one month.

 See mine is reported in KB.  Is yours KB or MBs?

You aren’t getting it.  The usage is NOT reported at the time used.  It is delayed by hours or days.  The 99 mb was used during the past 72 hours, not at midnight.  

Like when you write a check.  It doesn’t get posted to your account and deducted from your balance until the check is cashed and clears your account.  It might be the same night, or a week later.

FYI if you are on a 200 mb plan, you are probably paying more than current plans.    Please login to your My ATT app and click on “change plans” to see if there are cheaper plans with more talk, text and data.    Even prepaid has better options.

@creinha 80MB isn't much data these days (neither is 200MB!)...

What are you paying for that old plan?  $50 can get you 1GB with rollover and unlimited calling and unlimited texting. I can't imagine your old plan costs much less than that...

If you get any kind of discount it would apply to the first $30. 

@creinha As noted, 200mb of data is not much and I guarantee you that if ATT says you used the data, you did. If your phone has gotten any software updates or you have any new apps, it is very possible some setting has changed. It is also very possible that your WiFi connection dropped without you knowing it and your phone automatically switched to cellular. Somewhere on your phone is a record of what used your data. If you insist on keeping that small of a data plan, I highly advise you leave cellular data turned off and only turn it on when you want to use cellular data.

@creinha wrote:
YOU’RE not getting it. This has to be an invalid charge. There is no way with cellular turned off and only using wireless that I have used that much data. I’M USING A WIRELESS NETWORK, NOT CELLULAR DATA.

No, you're not getting it. Data IS NOT reported live, it could be from 72 hours before.

Are you saying you never have cellular on??

I didn't say you should pay for it.  I just said it's easy to use that much.

Changing plans isn’t an issue, paying for something I didn’t use IS. Even if it’s only $15.

Regardless of your current issues, I'm suggesting a plan that could be cheaper and better for you. 

If you can get more data for cheaper (or the same) why wouldn't you? Because you're distracted with this, you're not going to discuss saving money?

No carrier controls your phone.  It is entirely under the users control.  

You wrote this...”..I checked the setting in the phone and it apparently reset when I completely shut off cellular.”   No, it doesn’t.  On iPhone data would stay until you reset it.  On android data is reset at the end of each bill cycle.

“I did find an app that showed how much apps were using, but it did n’t show past usage, so I deleted it....”.  ????   The settings in your phone show data usage by application, and changing the date on android does show past use.  iPhone also shows in settings which app used data.  This isn’t something that can be deleted, it’s part of the OS of the phone.