Tunze ATO not working

[Coralgurl]

I checked it this morning, the bottom was clogged with hair (we have 2 cats and a dog), my reservoir is not covered....
I unplugged it, plugged it back in, it showed that it wanted to pump, but no water. The sensor works as I added a bit muchI gave it a shake and nothing. I completely unplugged it before I left for work, manually topped up the tank and will have to look at it tonight.