parental controls no longer working

I have a RAX54v2 and has always been using the nighthawk app to control all the devices. Everything has worked well until about a month ago when I noticed the kids were always on their devices without the time limits. I thought they were messing with the app, renaming devices, or changing their ip addresses somehow. I have their computer set to private home computer and the limit ip tracking turned off on their ipads. I use to be able to even pause the tv and that also stopped working so it’s all across the board and not just the kids’ devices. I’ve rebooted the router and deleted and added the app back on but it still doesn’t work.