Smartthings has hiccups from time to time, usually less than an hour - where it doesn't work, or works with a long delay, stuff like that. It doesn't happen much, but enough so that it's not news to anyone if they've been using ST for awhile. For our use, the last 4 outages have been around midnight - so I'm guessing they're maintenance, restarts or something to do with the regional servers, but who knows. It happens, rarely lasts long, be better if it didn't happen but that's not the world we live in yet.