Elko smart app issues - connecting Super thermostat

Has anyone else experienced problems using ELKO smart with homey lately? We have about 10 super thermostats that we control using homey. This has worked fine for some years. However one of the thermostats stopped communicating, and as part of the troubleshooting we tried deleting the ELKO app from homey and figured we’d reconnect all of the thermostats. But it won’t allow us to reconnect any of them now. As soon as it starts the normal connection procedure it gives an error, and never tell us how to connect or allows for enough time for a device to connect before saying that it couldn’t

connect.