Hey there! Great question. It's actually 2G. You can take a look at our terms here:
Simple Choice customers select how much high-speed data they receive under their service plan. Certain features, such as Music Freedom, some Binge On content, and data used by certain T-Mobile customer service applications, such as the T-Mobile My Account app and the T-Mobile Tuesdays app do not count against your high-speed data allotment. If your total high-speed data usage exceeds your selected high-speed allotment during a billing cycle, we may reduce your data speed to 2G speeds for the remainder of that billing cycle.
I'm sorry you were given the wrong info but now you can see where my response comes from.
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