I am having the exact same issue. I have tested all of the posted links for different shards (as seen here FAQ: How to find out what “shard” (cloud slice IDE URL) your Account / Location is on?) and jumped between the different tabs. I still get the “You don’t have any hubs yet. Please use the SmartThings mobile app to claim your hub.” I get the same error under “my locations”. I added a location and it changed nothing.
The hub is working and controlling lights, a/c, locks, etc.
I want to update the system so I can use some MCT - 340E sensors.
Am I missing something?
EDIT: After loging back in and out a few dozen times (and creating a smarthing account as opposed to a Samsung account, which affected nothing). It seemingly worked out of the blue.