Lost thermostat - recent upgrade to blame?

Before I start re-configuring, removing Honeywell thermostat from the system and adding it back - is support interested in taking a look at it?
Thank you.

Actually, rebooting the thermostat did the trick. Probably not even ST’s fault.

It’s very possible, but support does not monitor these forums. You need to write to them to start a ticket.

If you’re in the US, you can just write to support@smartthings.com

Or click on the support link at the top right of the community page.

You may find this interesting if this is the type you have: