History stats “Running hours”

I have a problem regarding history stats.
I’m using it to keep track of lights and pumps in my house. I’m using it for statistics regarding running hours, but something has happened with it now, it resets down to what it was After it’s been running.

I can’t find the problem and I don’t have anything in my log file.
I’m probably just missing something simple but for now i can’t come up with what it is.
I want it to continually count my running hours.