Last week I wasn’t able to select devices in the Smartthings app on my IOS device. I deleted and reinstalled the app and now I get a continuous loading wheel for my devices and it never actually loads them.
Try signing out and then sign back in.
Ive done that, then delete/reinstall and still nothing. When I log into the UI it shows no devices, but when I log into the IDE I see all the devices.
Check if you are on the correct location in the app. If you only have one location and your devices do not show in https://my.smartthings.com, you should contact ST support.
I had to provide temporary access to Smartthings and they had to do something on the back end to resolve the issue.