After upgrading Hubitat to version 184.108.40.206, it seems that scenes could no longer be controlled through Webcore. I tried re-adding them to the available devices list, did not help. Checked the piston logs and everything seems ok there. I can activate scenes through the Hubitat UI without problems. in the release log Hubitat stated that they have been refactoring and improving the scenes… Anyone or it is just me?
It would be good to show logs or what your piston is doing.
It is always possible an HE change, or a bug…