@cschave 

Is the extender broadcasting its own wireless network name (ex. mywifi-ext) or does it have the same name as your main router? Do you connect to the same network name even after installing the extender?

@Tony It has it's own unique identifier with a -ext at the end of the SSID. The extender is connected to the 5G SSID that I would connect with normally. 

Modem -> Wireless Router (SSID Chapter 4 @375Mbps) -> Extender (SSID Chapter 4 - EXT @12Mbps)

Conducting this all within a foot of the wireless router. Taking the extender further away from router does not impact speed. 

@cschave 

I would double-check the wireless network names as the TL-WA855RE only has a 2.4GHz antenna. If your router has a guest network, try enabling only the 2.4GHz and default and connect the extender to that in order to test the speeds.

@Tony I have connected the extender to the 2.4G network and now my download speed is 3.71 and upload at 10.1. 

@cschave 

The extender does not have the hardware to connect to the 5G. In this case it was set up and connected back to the 2.4G. Since the speeds continue to output slow I would suggest contacting our support to see if the device may be defective. If not done so, connect to your routers 2.4G network and see the speed of it. If that is slow too that would explain what the extender is outputting.