http://tpinkrepeater.net lets you connect to the TP-link wifi range extender’s management setup page via logging using the TP-link extender login credentials for TP-link extender setup or for configuring TP-link range extender:
If you are facing an issue trying to connect to tplinkrepeater.net;
Check for your internet connection which might be troubling in connecting to tplinkrepeater.net.
Ensure all the devices are tightly secured with Ethernet cable and properly connected to each other at WAN and LAN port.
A default web browser might be causing trouble as well to connect to tplinkreptear.net for login, use another web browser to sort the issue.
Lastly, try resetting the TP-link repeater to restore to factory default settings that certainly helps to connect to tplinkrepeater.net.