Apple Users

Stuff needs rebooting now and then.
Don't forget, your router is a link in the chain of DNS servers.

Just as a precaution, here are some good (simple) rules for keeping the router (mostly) out of harm's way.
https://routersecurity.org/
(I shortened the short list. There's more if you are so inclined)

* Change the password used to access the router. Anything but the default should be OK, but don't use a word in the dictionary.
* If your Wi-Fi network(s) is using the default password, change it, even if it appears to be random. A Wi-Fi password should be at least 16 characters long.
* If you are using the default SSID (network name) change it. When choosing an SSID, don't identify yourself.
* Wi-Fi encryption should be WPA2 with AES or WPA3.
* Turn off WPS
* Turn off UPnP
* Use a password protected Guest Network whenever possible, not just for guests but for IoT devices too.
* If the router has a web interface, Remote Administration is probably off, but since this is so very dangerous, take the time to verify that it is disabled. If the router is administered with a mobile app and a cloud service, disabling remote access to the router is unchartered territory. Lotsa luck.
* Periodically check for new firmware.

Apple stopped selling routers a while ago (airports) but has some good advice, having let go of the business.
Not just for Apple stuff. They just write in a less geeky way than most others.
https://support.apple.com/en-us/HT202068

I only mention this because wi-fi routers in the local monopoly ISP were "bricked" en-masse in recent times.