Same Problem. We have become very reliant on this singularity (Dangerous). All of my devices do not show up in the device list (Only 8 of them). However, when I go to Groups and add devices to a group all 85 of them show up including the duplicates and some triplicates. Just can’t delete them. The stupidity of allowing a duplicates and then later telling me “I found more than one device with the name xxxxx give them unique name…” How about not allowing duplicates in the first place. And now they have removed the ability to delete them. First they screw up (allowing duplicates) then they screw up a second time by remove the feature to fix the first screw up (Deleting Devices). My reliance on this is unfortunately large and Amazon may not actively support the fringe tech guys, however this is my main reason for paying for Prime each year.