Just got ours and even though we are waiting on a replacement processing unit. Ours doesn't want to see that the cleaning solution bottle is there. but a quick call to customer service and they got it all worked out. We love it and customer service was great. recommend the product as well as the company. Buy one and you would not be sorry. Well worth the cost. over all cheaper then the litter box and litter. I would spend about $20 a month on cat litter and with this product now looking at spending at most $50 every 6 months. I'll have to see how my cat go though cleaning solution. but one bottle last 3 months min and a 2 pack only cost $50 so should last at a min of 6 months. all depend on how many cats and how you let the unit clean. Cat activation doubles the life of the solution so. great buy and great value over time.