What procedure are using to connect them. Assuming your Ray is connected properly you first need add them as a room in the app. Then go to your Ray and select add surrounds. The app will detect them and guide you through the steps. If you are doing the preceding then what error message are you getting? 

Additionally, the “wifi” on the Ray should not be turned off. The surrounds communicate with the Ray on a unseen 5 Ghz channel. 

Remeber that the SL's need to be separated if they form a stereopair now.

So I’m getting the message “two compatible Sonos speakers are required to add surrounds. Make sure your products are powered on and connected to WIFI”

they are on and connected 

Thanks 106rallye I did just what you said and it’s working, ur a legend!