Hello. I will try to help you with this. I have found some information on the shift knob. Check to see if this looks similar to what you have installed on your vehicle. There is a screw to tighten on the shift handle according to this instructions. Maybe it has become loose or fallen out. Also, if you need to replace the handle due to wear then the plastic panel under the shifter lifts out and is help on with clips and the wiring connection should be there. Just be cautious during removal as not to damage the shift selector.
Also, is this a stick shift or manual trans as this will make a difference. The instructions are for the automatic. I am also including the instructions for the manual.
Manual trans.The wires should be under the shift boot.
Hello Ryan. The shift knob itself is the holder. It press fits onto the shifter shaft. If it has come loose and will not stay secured then it will need to be replaced. To secure the shift knob usually it only takes a good hit downward on it from the top. As for the wires, Can you lift the shift boot off, it is only held by clips and should come loose fairly easily. Under this you should see where it is connected. You can then guide the wires into place or pull them back down so they no longer get jammed in the shifter. If you can give me the last seven of the vin I can check for a price on the shift knob for you at the dealership. Thank you and let me know how it goes and I will try to help you further.
-Roger
BMW Mechanic
Level 1 BMW Master Certification, 9 Years Dealer experience, Team Leader, Shop Foreman