I like my Xshot XSP1 hand-held monopod. It's light and telescopes to a useful length. I mostly use it with a GoPro camera. But the way it gets all loose and wobbly after a few days of use drives me bonkers.
To tighten it, peel back the rubber mat under the mount, push aside the rubber cement that holds the mat, then use a tiny Phillip's screwdriver to tighten the screws. See the picture below.
Put everything back together afterwards, but be prepared to do it again in the near future. And then again, after that. You might try replacing the screws with bigger ones to see if they hold better. I haven't done so myself.