Dimming feature doesn’t work on GE Zwave switch

I am new to Homey Pro, I did search topics and could not find previous post. I am testing Homey Pro, I have been using Alarm.com Quolsys IQ panel2. I have a GE Zwave switch that controls a fan, it was able to connect but it won’t “dim” or reduce fan speed using the dimming option. It had no issue reducing fan speed on Quolsys panel. Please advise.