If the wall is metal or concrete or has metallic wallpaper or even has water pipes running through it, it may literally just be a range problem.
When the devices are in the same room as the hub they work when you tap the tile in the SmartThings mobile app? But they don’t respond when they’re on the other side of the wall?
If so, it sounds like range. You’ll need to do something to get the signal through the wall.
This is a common problem in cement and adobe buildings. Sometimes even with brick. Typical US construction doesn’t usually have this issue because there’s actually a lot of airflow through most of the walls.
But before we get too far into possible solutions, let’s just make sure I’m understanding the problem correctly. 