According to your description, the extender has been set up successfully. Please double check the light status on your extender, once you have the 2.4G light on and solid green Wi-Fi light, it means the extender has connected to your host router's 2.4GHz network and in a good location. 

In normal case, after we set up the extender successfully, it will copy the same Wi-Fi name and Wi-Fi password from your host router, the default TP-Link Wi-Fi name will disappear. Please connect to the host router's Wi-Fi name, you will get a stronger signal strength. For your case, there should be a 5GHz network comes from the range extender, it has a smililar name with your host router and a 5GHz as postfix. The 2.4GHz name should be the same as your host router's Wi-Fi name. 

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