I gave the extender an other SSID

post how this is possible, extenders are to extend or repeat a signal, so that means extending your SSID, you can only change SSID on AP mode
this is the tuto to repeater or extender
1-hard reset TP-Link wireless access point to factory default http://www.tp-link.com/en/article/?faqid=202
2-How to Configure my Range Extender on Windows http://www.tp-link.com/en/article/?faqid=357 in case you use a MAC How to Configure my TP- LINK Range Extender on MAC http://www.tp-link.com/en/article/?faqid=408
some are IP 192.168.1.254 others 192.168.0.254

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