Very good question, The most common reason a method will stop working for someone is that they are out of balance. The easiest way to test this is put your hand on top of your head palm down and do the sway test. If you go foward generally you are in balacne if you go backwards you are out of balance and will be getting the wrong answers during your testing. If you put your hand on top of your head palm faceing up you should lean backwards meaning you are imbalcne and foward means out of balance.
If you test out of balance there are a few ways to get back in balance the easiest is to think of unconditional love and gratitude for a short while and retest your self. If that does not work there is another method that works everytime, however it is hard to explain in writing. You can call me at 971-325-1153 and I can explain it in detail, or video chat and show you how it id done.
Best of luck.