Does anyone have any experience with Concentric volume/tone knobs? I bought my first electric on Sunday (a Squier Vintage Modified Jazzmaster Special) which has them on, and the top part of one of the knobs just fell off out the blue while I was playing. It now won’t stay on, and I can’t figure out how I can reassemble it properly (obviously supergluing it or something isn’t an option because I will want to use it in future). I've uploaded a couple of pics, hopefully they work Does anyone have any advice? Trying not to panic here, haha.

Thanks in advance

The little hole on the side of the knob is for a set screw. Hopefully you haven't lost it, though it sounds like it fell out somewhere along the way. Check your carpets for a little screw that goes in there, or make a trip to a hardware store to find one that fits. Put the knob on the shaft and tighten the set screw. Easy fix!