Sounds like the screws in the troll head may be loose. The only way to get to them is to remove it, not as hard as it looks. Remove the wire ramp above the troll, flip the table up, disconnect the cables, remove the locator nut and two others if I remember correctly. Then work it gently from above pulling it out the top of the table.

After you do it once or twice you can do it in minutes. If the left one is loose I would suggest pulling the right one and making sure they are tight as well. Some other threads on this process are available on Pinside and RGP. Fix it now before they work completely loose. Check the heads for cracking around the screw holes, very common, if they are broken just replace them.

You gotta take it apart no way around it. U might have to replace switch If anyone knows where to get new troll switch, not entire assembly please me know.

I prefer to remove the assembly from below. Saves you having to remove the wire form.

Just gently pry up the troll flap and lift him up. Once he's up, you can slide a thin piece of metal under the black bracket, between it and the playfield, so it can't drop back down. I have a super thin small flat wrench that came with something from IKEA and it slips in there perfectly. A popsicle stick or small Allen wrench would work as well.
Once the troll is held up, just pull the two spring clips on either side with needle nose pliers (don't drop them) and the flap just lifts right off.
Now you can remove the entire assembly from underneath with just 3-4 hex screws. Much easier to work on the assembly this way I find.