It interesting you mention updates. My router’s app updates every few weeks, but the actual router updates maybe twice a year.
When did you last update your Wifi firmware?
Just FYI, A'goners, that routers often need patches to remain secure over their lifetime and old routers may no longer even be supported and therefore, there would be no new patches for new security holes.
If you've never checked your router's firmware for updates now may be a good time. In my case I have 2 network devices and both have needed security patches to keep them safe. This is in addition to making sure your router is not accessible from the outside world.