"This device is blocked by access control in the router."

You'll need to use a device that isn't blocked from access control to make changes. Here's the steps on how to allow/block devices using access control for the nighthawk routers. 

https://kb.netgear.com/24830/How-do-I-use-access-control-to-allow-or-block-devices-from-accessing-the-Internet-on-my-Nighthawk-router