Netgear R6350 at an apt w free wifi

I'm completely lost with my internet connection ever since I got this router. It worked fine before and I decided to change the Network name and the password and now I have nothing but a headache and confusion. It's free wifi at my apt. I call the wifi business and they say I need to talk with Netgear. I'm not sure what to do. I just want wifi back. Easily. What did I do wrong and how do I fix it? Please help me.