Neptune auto top off failing

[Llorgon]

My neptune auto top off seems to be broken or is now failing.

It is standalone, had it for about 6 months with no issues.

This morning I checked my sump and found the water level was low. Checked my controller cabinet and the ATK didn't have a warning light on so I unplugged it and plugged it back in which got it filling again, but now it won't stop. Hits the first sensor and keeps going, hits the second sensor and keeps going. I even manually lifted the float swift as far up as I could. LED is green and pump is still going.

I wiped off the sensors and wiped off the float switch. Doesn't appear to be anything on them.

is my auto top off broken or just needs a good water and vinegar soak and scrub?