Why can't I get data on my unlocked S4?

[AC Question]

Why can't I get data on my unlocked s4

I have just purchased an unlocked s4 into which I have put my o2 ireland sim and I can make and recieve calls, but sadly no data unless i conect to wifi. I am not technical but have i bought a dud phone or is there a way to fix this? thanks

 

[B. Diddy]

Re: Why can't I get data on my unlocked s4

Welcome to Android Central! We need to know the exact S4 model, because there are bunch of variants intended for different regions of the world and/or different carriers. These variants often have different network band compatibility. You need to compare the bands that your S4 uses with the ones that O2 uses, and see if they match. If they don't, then you can't use the phone to access mobile data.