works, but still creates Infinite $digest Loop error

trying to fix [this infinite digest loop error](https://docs.angularjs.org/error/$rootScope/infdig?p0=10&p1=%5B%5B%22fn:%20function%20(c,d)%7Bvar%20e%3Da(c,d),f%3Db(e,c,d);return%20y(e)%7C%7Cb.$stateful%3Ff:e%7D;%20newVal:%2015;%20oldVal:%2013%22%5D,%5B%22fn:%20function%20(c,d)%7Bvar%20e%3Da(c,d),f%3Db(e,c,d);return%20y(e)%7C%7Cb.$stateful%3Ff:e%7D;%20newVal:%2017;%20oldVal:%2015%22%5D,%5B%22fn:%20function%20(c,d)%7Bvar%20e%3Da(c,d),f%3Db(e,c,d);return%20y(e)%7C%7Cb.$stateful%3Ff:e%7D;%20newVal:%2019;%20oldVal:%2017%22%5D,%5B%22fn:%20function%20(c,d)%7Bvar%20e%3Da(c,d),f%3Db(e,c,d);return%20y(e)%7C%7Cb.$stateful%3Ff:e%7D;%20newVal:%2021;%20oldVal:%2019%22%5D,%5B%22fn:%20function%20(c,d)%7Bvar%20e%3Da(c,d),f%3Db(e,c,d);return%20y(e)%7C%7Cb.$stateful%3Ff:e%7D;%20newVal:%2023;%20oldVal:%2021%22%5D%5D).

does not work :cry: