Nighthawk Keeps Blocking My Device Despite Constantly Reapproving

My Nighthawk keeps blocking my Kindle Paperwhite over and over. I have tried changing it back to approved in the app, and I have logged in through the browser to manually add it to the approved devices list from the blocked list. I have also tried restarting the router, as I have to restart it constantly anyway because the internet likes to randomly drop out.

I'm about at my wits' end with this. Does anyone have any advice or solutions, aside from smashing it with a baseball bat and going with a different brand? 😂

Thanks!

Hardware Version RS400
Firmware Version V1.5.0.34_10.0.33
GUI Language Version V1.5.0.34_2.1.38.1