[SOLVED] Need Help with rule an Null Exception Error

Hi i am Using OH2 on Win10

I try to send a Number value to an item created from String
The problem is that the new Item does not accept my value
What i am doing wrong?

Triggering Items is for example (I have several Items called: Sonoff_xxx_xxx)

Number Sonoff_TV_Today "Energie heute [%.3f kWh]" <energy> (gkwD) { channel="mqtt:topic:f52cfe9a:eToday" }

and i would like to send the value price to a new item created by rule.
The name of the new Item is already set in my items as:

Number Stromkosten_TV_Today "Stromkosten Heute[%.3f €]"  <piggybank> 

Here is my rule

rule "Update Stromkosten" //Berechnet Stromkosten für jedes Mitglied
    Member of gkwD received update 

var Number price = (triggeringItem.state as Number) * strompreis // strompreis is declared as val  strompreis=0.26
val membername = triggeringItem.name.split("_").get(1) //Schlaf, TV, Trock, etc.
var  ending = triggeringItem.name.split("_").get(2) //Today, etc.
var  newItemName = ("Stromkosten_"+membername+"_"+ending) 

logInfo("Stromkosten", "Result Price:" +  price)
logInfo("Stromkosten", "Result membername:" +  membername)
logInfo("Stromkosten", "Result ending:" +  ending)
logInfo("Stromkosten", "Result itemName:" +  newItemName +" "+triggeringItem.state+" "+triggeringItem.name)
sendCommand(newItemName, price)


Logs seem to be ok except the sendCommand

2019-09-25 12:46:23.188 [INFO ] [e.smarthome.model.script.Stromkosten] - Result Price:0.00390
2019-09-25 12:46:23.189 [INFO ] [e.smarthome.model.script.Stromkosten] - Result membername:TV
2019-09-25 12:46:23.191 [INFO ] [e.smarthome.model.script.Stromkosten] - Result ending:Today
2019-09-25 12:46:23.192 [INFO ] [e.smarthome.model.script.Stromkosten] - Result itemName:Stromkosten_TV_Today 0.015 Sonoff_TV_Today
2019-09-25 12:46:23.193 [ERROR] [ntime.internal.engine.RuleEngineImpl] - Rule 'Update Stromkosten': An error occurred during the script execution: Could not invoke method: org.eclipse.smarthome.model.script.actions.BusEvent.sendCommand(java.lang.String,java.lang.String) on instance: null

Could you help me to solve my problem?

Thank you

Counter intuiively

sendCommand(newItemName, price.toString)

Maybe more efiicient:
postUpdate(newItemName, price.toString)

Thank you so much.
It works