Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Doesn't Work

Agree with other reviewers. I owned an earlier model which worked well, and purchased this one when it broke. The design has changed to the detriment of the product. If you fill with litter as outlined in the directions the "rake" goes over the waste and smashes it up making it more difficult to remove. If you fill it with more litter than recommended, the motor lacks the power to push through it and move the waste. Tried to solve the problem by buying "premium" litter, but to no avail. Three kinds of litter later, it still doesn't work. Finally, i unplugged the litter box, took out the rake, and started manually scooping as i would with any other litter box. This works best! Unfortunately, the price of the automatic litter box as compared to a plain plastic tray is ridiculous.