Recovery is not seandroid enforcing?

So I am trying to root my Galaxy S6, Sprint model, Android 5.1.1, running the latest OGA firmware. After seeing people's success stories about how the previous version of UniKernal worked fine with the new update, I decided to root. When flashing TWRP 2.8.7.0 to the Galaxy S6 I get the "recovery is not seandroid enforcing" message in red at the top of my screen. Holding Volume Down and Power resets the phone and it boots up like normal. How do I get rid of the error?