The value of the local variable DailyPowerProductionAPS is not used

When I start OpenHAB (2.5.11) I see this INFO in the log, but I fail to understand why:

2021-01-31 13:19:49.494 [INFO ] [el.core.internal.ModelRepositoryImpl] - Validation issues found in configuration model 'power.rules', using it anyway:
The value of the local variable DailyPowerProductionAPS is not used

It is used:

rule "Daily power production calculation APSystems"
when
    Item ZonnepanelenWh_schuur changed
then
    var DailyPowerProductionAPS = ZonnepanelenWh_schuur.deltaSince(now.withTimeAtStartOfDay)
    //logInfo("Daily power production APS ", "DailyPowerProduction APS = " + DailyPowerProductionAPS)
            if ( DailyPowerProductionAPS === null || DailyPowerProductionAPS == NULL) {
        logInfo("Daily power production calculation APSystems", "DailyPowerProductionAPS = " + DailyPowerProductionAPS)
    } else {
        APSACLifetimeEnergyToday.postUpdate(DailyPowerProductionAPS as Number)
    }
end

Normally VScode would also display this error if it’s true, but there is no error in VScode.

I use the same code for my other solar panels and that doesn’t give me an error:

rule "Daily power production calculation SolarEDGE"
when
    Time cron "0 0/1 * 1/1 * ? *"
    //Item SE7KACLifetimeEnergy changed //Every few sec is too much, changed to every minute
then
    var DailyPowerProduction = SE7KACLifetimeEnergy.deltaSince(now.withTimeAtStartOfDay)
    //logInfo("Daily power production", "DailyPowerProduction = " + DailyPowerProduction)
        if ( DailyPowerProduction === null || DailyPowerProduction == NULL) {
            logInfo("Daily power production calculation SolarEDGE", "DailyPowerProduction = " + DailyPowerProduction)
        } else {
            SE7KACLifetimeEnergyToday.postUpdate(DailyPowerProduction as Number)
        }
end

Perhaps it’s in some other rule, due to copy/paste accident.

I searched for that string in VScode, it only occurs 7 times, and that is in that specific rule.