Energy dashboard: energy cost entity not saveable

Hi, when i try to add an entity that tracks the cost of electricity, the save button does not lit up. the weird thing is that for gas cost i did the same and that works without a problem.!

here is how i set up the helper entity. it’s a float and the unit of measurement is €/kWh. should be ok right?..

has anyone an idea? or is this a bug?

for anyone interested. i made an automation that uses some input fields, and when i get the new tariff for next period, i just enter those costs and when it activates, so it automatically changes it at the right time.
image

Apparantly it is a bug that removes the entity. this will be resolved in 2023.8
see this solution: Energy dashboard: energy cost entity not saveable · Issue #17369 · home-assistant/frontend · GitHub