I have had the g1 one month and am happy with it. However a couple times I have found that even though the floor is wet and cleaned there is no water being collected in the dirty tank. It happened today even though I had used the mop normally , I left it for a few minutes and went back to it. No water was collected. Then I did a self clean and no water was collected at all during the self clean. I put water on the floor, mopped it and then it worked fine. I did the self cleaning again and it worked. Is this normal? Did I do something wrong or is it the machine? Thanks