You're jumping to a bit of a conclusion also; These differing results didn't happen of the course of years, or even months. They were separated mostly by weeks, and in some cases days. The test isn't reliable.
Also, I'm not trying to come up with a "gotcha". This isnt a debate. Best case is enough people inform you that these personality tests are malarkey that you do some self reflection. Worst case is that I wasted a bit of my time.