Many devices not listed in the ADT Security Manager in the SmartThings App

Installed an ADTSmartThings panel and using my iphone I set up 2 door sensors and a motion sensor. At that time there were Arm (Stay) and Arm (Away) buttons in the “Home Security” area of the app. This screen also has “Favorites” in which I added the 3 sensors. After some time, the “Home Security” area disappeared along with the Arm icons. I could only arm/disarm from the panel. I then added 2 more door sensors and now the “Home Security” area is back and when I touch the > and get to the Security Manager panel, the new devices are listed, but the original ones are not. Touching the settings icon takes me to Security Settings and I can see the new sensors, but not the old sensors.

How can I get the old sensors to appear back in the Security Settings, and Security Manager panels?