Lambda functions not executing from a rule and null reported in log

Setup, Configuration and Use Scripts & Rules
,
3

I added a new lambda function and tried again with the same results so I don’t think it’s related to the ‘1’ value in the parameter.

val lambda2 = [ GenericItem sensorX, GenericItem switchX |
    logInfo( logName, sensorX.name + " state is " + sensorX.state )
    logInfo( logName, switchX.name + " state is " + switchX.state )
    true
]

rule "test sensor 1"
when
    Item test_sensor1 changed
then
    logInfo( logName, "starting: 'test sensor 1' rule...")
    //lambda1.apply( test_sensor1, test_switch1, 1 )
    lambda2.apply( test_sensor1, test_switch1 )
    logInfo( logName, "ending: 'test sensor 1' rule!")
end

openhab.log

2020-02-01 16:53:30.626 [INFO ] [eclipse.smarthome.model.script.DEBUG] - test_sensor1 changed from: OFF to: ON
2020-02-01 16:53:30.627 [INFO ] [eclipse.smarthome.model.script.test1] - starting: 'test sensor 1' rule...
2020-02-01 16:53:30.629 [ERROR] [ntime.internal.engine.RuleEngineImpl] - Rule 'test sensor 1': null