Fix Philips Sonicare Toothbrush - loose tip or not vibrating appropriately

My Philips Sonicare toothbrush’ tip became loose and was not vibrating effectively. This video shows how to open the toothbrush and check the root cause of the problem: a simple screw needed to be tighten. I also recommend to add some Loctite to it so it stays in place (not shown on the video but some people recommended this). Hope this helps fixing your toothbrush.