The system has been unstable for about a week, including database corruption and random mode changes. It seems likely that’s what you ran into unfortunately.
Official status page:
Discussion thread:
SmartThings Community,
This past weekend, performance of the SmartThings platform began to degrade due, primarily, to high load on the database and messaging infrastructure. As a result, some of our customers have experienced degraded access to and control of Smart Home Monitor, Routines, and other SmartApps within the SmartThings mobile app.
We are actively investigating the root cause of this critical issue in an effort to resolve current issues and prevent future incidents from occurring. This effort includes dedicated teams focused on near-term stabilization of the platform as well as teams focused on expanding the platform architecture. Despite this effort, we recognize the degradation impacts many of you individually, and we are sorry for the inconvenience this has caused.
Moving …