Help needed - Mobile data is off (phone says 0mb) but there is 0.0051mb data that carrier registers.

[swannlake]

Any help at this point will be appreciated.

Mobile data is off on Samsung. Background data is also turned off. All updates are set to 'WiFi only'. Yet per month, there is a tiny amount of data each month that is being charged on a tier system (carrier does not charge per mb). What could be causing this?

Update: I checked on mobile data and it still says 0 mb used on the actual phone, yet the carrier is once again registering the tiny amount of data. I re-checked all the apps to make sure mobile data background usage is still restricted, and on a few apps, they are now enabled (now blue and not grey). Could something force these apps to enable mobile data and even though the phone says 0 mb - that is the reason for the data leakage? I have once again disabled background data. (Note: this did not happen on the previous month, so there was still data leakage and background data remained off).

Tried contacting the carrier, they are of no help. They say the data usage is valid.

 

[Rukbat]

That's 5.1kb. Unless there's a difference in what they charge you between 0 and "anything", I wouldn't worry about it. (5.1 kb is about 1 second of voice. It's about as close to nothing as you can get without it being 0.)

 

[swannlake]

Even with such a tiny amount, on a tier system, the carrier charges $10.
Any ideas as to what other setting could be causing this?