@Kevinbsjajak,

In order to get a better idea of what is going on, I am going to need more information regarding your network setup. How have you configured the Range Extender, to me it sounds like it is working and just using the same SSID. 

"Wont Appear in Any Device" - What Device? The network router, the phone setup?

Were you able to start or complete the initial configuration process? What method did you use to setup the RE?

  @Kevinbsjajak,

Are you able to access the settings for the Range Extender? The RE should have had you connect directly to the device's wireless connection during setup, is this wireless network STILL available?

I would first recommend resetting since if what you say is true, the lights aren't lining up with what is happening. Unless, the lights are only indicating that it is connected to the network, not that it can access the internet. Also for your information, if you set up your range extender to use the same SSID of the main network, the wi-fis will not be visible in your list of networks, as your device will automatically switch. However, since the ethernet says no connection, we know this is another issue.

You can navigate to tplinkrepeater.net on your PC that is connected to the RE to find the Web Interface for your Range Extender. In these menus there are many different options and methods for extending various networks. If the interface indicates that the extender is connected to your network, and all the settings look correct; there may be a setting on the router that is conflicting.

  @CARTER58,

Yes this is how an RE works by default, you can change this through the app or the Interface.

An RE Serves to extend the network (Settings and SSID) beyond its original reach. If you are curious, you should be able to download a wifi analyzer app on your phone and see the changes in connectivity and speed as you move closer and further away from the RE.