No network after upgrading Sony Z3 Compact to marshmallow

I recently upgraded my Sony Z3 Compact to Android Marshmallow and noticed something really odd. When not on WiFi, I wasn't getting any push notifications or any updates. I'd come home or get to work and then my phone would light up and beep like mad. Later, I discovered that there was no network connection on the mobile network. I could make calls and receive texts, but the data connections just wouldn't work. Luckily, it's an easy problem to fix.

Go to Settings -> More -> Internet Settings   and then choose Accept. You'll need to be on WiFi to do this, but it should fix the problem. Unless you're on T-Mobile and just can't get service anyway. Here's a video showing the steps:
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