Can't remove utility meters, red exclamation mark

Hi. I’ve a couple of helpers (utility meter) but I can’t seem to remove it anymore from the gui.
It gives a red exclamation mark and when I click on it, I get the settings screen (see screenshot). When I click Send, nothing happens. When I click off the periodic reset, nothing happens either.

Also when I choose another entity as input, the stats stays the same.

How can I remove these entities/ or solve the red exclamation marks?
Thanks

Nobody has a solution?

I have the same problem. I think I deactivated the helper and now it no longer has an entity. I can only change the settings now, but I can’t delete it.