Pokemon only appearing half the time.

I got a new phone (Huawei honor 5x) and I got the basic Cricket Wireless plan to play Pokemon go. But now when I go to all the spawn points in my town when I use my tracker only half the time the Pokemon will actually spawn. And I always have to restart my game to get my local cluster spawn. I don't think I'm shadow banned because I was able to catch a Flaffy yesterday after I went to its location and restarted Pokemon Go. anyone else have similar problems?