Customer experience is something we take very seriously, Teako10. It's important to know how your phone uses data so that we can help identify where the usage in question is coming from. We simply provide your devices the data they request. Certainly unlimited data is a great way to not have to worry about your usage, but it's not the right plan for everyone.
There can be a number of things happening that have caused this spike in usage. The first is your daughter may believe she's connected to Wi-Fi when she is not. Also, if she is connected to Wi-Fi and the cellular data signal is stronger the phone may be defaulting back to cellular data.
What make/model device does your daughter use? Was there any recent changes to the device?
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