Can't activate my Galaxy S4?

[AC Question]

I bought a Galaxy S4 off someone over the internet and I can't activate it with my new at&t sims card?

 

[srkmagnus]

What model S4 did you purchase? Not all are the same, so go into system settings > about phone > model number. Let us know what it says and we'll try and figure out why it's not being activated.