New models of Tp-link Extenders are equipped with the Mac Filtering option that allows the user to control the device currently connected to the Range Extender. A user can control the amount of bandwidth that a specific device is going to receive that eventually gives control over the amount of Wi-Fi signals that are being transmitted to other wireless devices. Before you start configuring the Mac Filtering feature through the tplinkrepeater.net window, a user has to make sure that the Range Extender has successfully connected to the router. Also, check that on which mode your Tp-link Range Extender is operating.
https://setup-tplinkrepeater.net/