I bought a samsung s5 G900A

[s5 G900A]

I did NOT want an update from my kitkat version to lollipop on 10/30/2015, I tried to stop it for a full day, from taking apart the cell, turning off wifi and data, even clicking on remind later, I've been hung up on by an AT&T tech person also....how can I root my phone to permanently deny AT&T any access to my phone?

 

[the tall guy]

Hi, please check out the AC root section, also have a look on YouTube for tutorial videos - Rooting your Android | Android Central