I’m having the same issue, but it seems the only people responding are people with the issue. No one from Smartthings or Nvidia are even joining the discussion.
Look at page 16 of the following thread
https://forums.geforce.com/default/topic/1027516/shield-tv/shield-experience-upgrade-6-1-for-shield-tv-released-10-30-2017-/
https://forums.geforce.com/default/topic/1029365/shield-tv/no-internet-connection-on-startup/