Hi,
quick one,
in: https://graph.api.smartthings.com/device/list
i have quite a number of things listed inside as an unknown type and it can’t be remove, because when i press device detail, it show me:
Oh No! Something Went Wrong!
Error 500: Internal Server Error
anyone have any idea how to remove this?
Thank you
AnD
time to contact support@smartthings.com they will can help remove them for you.
Thanks, I will try to contact them 
I had the same issue. Contacted Support and they got rid of them for me the next day
I got unknown devices when I tried to cheat the process when adding new devices. When adding GE Link bulbs you’re supposed to turn them on individually as each one is detected in turn however, I went round and turned on three switches that turned on a total of 12 GE Link bulbs at EXACTLY the same time.
The hub picked up about 9 of them and the rest appeared as unknown devices, note that this IS NOT a fault with ST, you’re not supposed to do this but I was seeing how cheeky I could get. Anyway, if I then went back and started the ‘add new device’ process and turned on those bulbs again it would replace the ‘unknown devices’ with the bulbs that it ‘missed’ and the unknown devices would disappear.
I bought a couple GE bulbs. Both came up as ‘unknown’, even after multiple pairing attempts… I don’t need that kind of aggravation. I returned them and got Cree bulbs, which pair correctly on the first attempt.
I was having problems pairing my new GE Link bulbs with my V2 hub. They kept showing up as “Unknown” device types. Here’s what I did to fix them:
First, I paired them, named them as unknown devices.
Then logged into “https://graph.api.smartthings.com”.
At this point do the following:
My Devices
Click the name of the new GE Link bulb (the name you gave it).
Click “EDIT” in the bottom left.
Change the “Type” drop down to “GE Link Bulb”.
Click “Update” in the bottom left.
Now re-open the app in your smartphone. The bulb should show up as a bulb device.
That’s a different issue to the one I was having at the time.
Newer GE bulbs do pair as an unknown device due to differences in the firmware and the fix as you have noted is spot on.