Rule to check z-wave switch command and auto switch off after timer elapsed

Setup, Configuration and Use Scripts & Rules
,
1

Im trying to do this simpe job by one rule and one item file.

basic.items as follows

Switch Smart6   "Smart6 WallPlug"  <switch>  {zwave="29:command=switch_binary" }

29 is the z-wave network node Id i hope :confused:

basic.rules as follows…

var Timer timer = null

rule "Timer Demo"
when
    Item Smart6 received command
then
    if(receivedCommand==ON) {
        if(timer==null) {
            // first ON command, so create a timer to turn the light off again
            timer = createTimer(now.plusSeconds(2)) [|
                sendCommand(Smart6, OFF)
            ]
        } else {
            // subsequent ON command, so reschedule the existing timer
            timer.reschedule(now.plusSeconds(2))
        }
    } else if(receivedCommand==OFF) {
        // remove any previously scheduled timer
        if(timer!=null) {
            timer.cancel
            timer = null
        }
    }
end

I struggle with that simple thing now for hours but i cant get it work.

Any ideas whats wrong?