@Fkadu
May I know double check what's the model of your Tp-link device?
If the Power Led does not stay on, please try a factory reset on the extender as mentioned in the FAQ below and see if that makes any difference:
How to configure my 11N Range Extender via Web GUI?
Does range extender broadcast a Extender or TP-Link extender Wifi SSID after reset?How long the extender has been worked?