The Fibaro dimmers can sometimes be controlled by the local (wired) switch but most of the time this does not work. If the dimmer power is reset (turned Off and then On) the switch will work for a while and then stop working.
The dimmer is being used with Z-Wave controller software such as HomeSeer or Indigo via a USB-Z-Wave dongle.
There is a known issue where the Z-Wave software controller does not allocate any value to the Fibaro Dimmer's Association Group 3. This association group must be associated with the Z-Wave controller.
Ensure that the dimmer's Association Group 3 is associated with the Z-Wave controller.
You can also test this by setting the Dimmer's parameter 10 to 0 - if this resolves the issue, then you need to associate the dimmer (group 3) to the controller.