Hello @Salaho ,

Thanks for contacting our community.

Please try the following steps:
1. Ensure the router's Wi-Fi is working properly. Connect a device directly to the host router (via Wi-Fi or cable) and check if the internet works from there.
2. Restart both the router and the extender. Power them off, wait 30 seconds, then power them back on and check again.
3. Upgrade the extender's firmware to the latest version. Outdated firmware can sometimes cause connectivity issues. You can do this via the Tether app or the web management page at http://tplinkrepeater.net.
4. Check for MAC address filtering or Access Control on your host router. If these features are enabled, they may be blocking the extender. Please contact your router's support team for help disabling them.
5. Check the IP address settings. Compare the IP address obtained from the router and the extender. If they are not in the same network segment, you may need to enable the DHCP server on the extender. You can find detailed guidance here: What's the solution if my TP-Link range extender can't connect to my router properly?