The real BPM of my track is 98, however I am getting 198. Or the real BPM is 60 and I get 100. Can you please tell me what the problem might be?

Our analyzer is tuned for "popular music," where 60 BPM is less likely than 100 bpm. The other case is a "double" case, where twice the amount of the real BPM was detected. If you don't expect a BPM value of, let's say above 150 bpm, then you can just simply cut it in half if you get a value above 150.