Trouble with Knn

I've build a knn model for regression, but isn't work. When I call for a prediction, with a set of numbers, the answer always be the same value, like this >>> In = 0.742781 || Out = 0.917355> In = 0.557086 || Out = 0.917355> In = 0.19518 || Out = 0.917355> In = 0.9759 || Out = 0.917355> In = 0.09759 || Out = 0.917355 the model is setted to regression (setIsClassifier(false)) and the Algorithm Type is Brute Force (The KdTree isn't work too, showing a error). Please, guys. I need so much this help.