Root [TMobile] No service

[watchmexplode92]

So I recently purchased a used T Mobile S5 from amazon, and I figured it would work with my current sim card. I put it in but when I turned the device on it would not connect to the network. I flashed CM 12 thinking that it would fix the problem but i still have no service. I've tried manually connecting through the available network settings but it always fails, saying unable to register on network. Do I need a new sim card? Or is it the device itself?

 

[Fox Mulder]

You might have to call customer service and register the new device on your account. At least that's how it works with Metro.