I have a foldable e-bike, and I had to replace the PAS (Pedal Assist Sensor) disk as my old one broke. I bought a new unit of the same size from Amazon, which had 12 magnets. I removed 6 magnets to match my old unit. I had it installed at a bike repair shop. Now it works very intermittently. Before, I would see 2 bars of power assist on the screen at the controls level, but now I only see 1 bar, and most of the time, it comes and goes. What do I need to do to get it back to the way my bike used to work in power assist mode? I'm looking forward to any suggestions.