There were a number of changes and improvements to the handling of the enabled property over the last couple of years. The last fixes to go in regarding this property were added in 4.0.26. Specifically, that change was around Enabled via bound properties.
Given you are running Ignition v8.1.31, I would recommend upgrading to the latest version of Engine which is 4.0.21. The compatibility chart is here: Ignition Compatibility with Cirrus Link Modules - MQTT Modules for Ignition 8.x - Confluence
Even better, if you can upgrade Ignition, I would recommend upgrading to 4.0.29 of Engine. There are no known issues around Enabled with this latest version.