I believe I received it for my S4 (AT&T) about 3 weeks ago, and it's having trouble installing for whatever reason. I'm pretty peeved it took so long to get it

I believe I received it for my S4 (AT&T) about 3 weeks ago, and it's having trouble installing for whatever reason. I'm pretty peeved it took so long to get it and will probably switch back to Apple the next go around.