Help needed! Energy database costs calculation wrong, after investigating everything

Thanks for your info.
I think i got it working, i will also wait again from now on 30 minutes, as my new device what i created had + instead of * so if that works, i need to try how i can import the old data into this new device. but lets wait.

I also will report at 12:00 and see if it did calculate, but i think its correct.
I’m using a total cost device, using this template

So this (device) entity is called sensor.calculategaspricetest, this calculated the value i use in my helper

this is the template from the helper.

  - sensor:
      - name: Today GAS Total Cost
        device_class: monetary
        state_class: measurement
        unit_of_measurement: EUR/m³
        state: >
          {{ (states('input_number.gasprice')|float(0))}}

this is the helper

this is the total entity calculated with the template from above and the helper

      - name: "GasTestCostCalculatorTotal"
        device_class: monetary
        unit_of_measurement: EUR
        state_class: total_increasing
        state: >
           {{ (states('sensor.gas_helper_test')|float()) * (states('sensor.today_gas_total_cost')|float())}}

SO the above one creates the total EUR what i use in the energy dashboard, and like now it looks ok.
Fingers crossed.