R6020 can not connect to wifi

Hello,

I bought a Netgear R6020 from Walmart. It is not allowing me to connect to the internet on any device using wifi, and is popping up with a pink error message that state "403 forbidden"

It looks like a lot of people have had similar issues. But i cant find a straight answer on how to solve this problem. I am not a tech guy by any means.

Everything else is working fine, and I know my signal is strong because I am hardwired in now, but wifi will not get passed that "403 forbidden" issue.

Someone please assist. 

Thank you