Hello, I am trying to set up my friend's Squier J Bass with lower action to improve playability. I know how to adjust basses as I have build some electronic instruments. I am stuck because the bridge pickup will not raise or lower. I have loosened the screws and have tried pulling up on the pickup and it will not move. Normally when I push on a pickup it will depress into the body a bit, but this one will not budge. It is playable and decent as it is, but it could be so much better. TLDR: The bridge pickup of a Squier J Bass will not move up or down. Does anyone have an idea as to what could be causing this?