How do I unblock my garbage disposal?

Did you hit the reset button?

There should have came with it a 'Special wrench'. You use this wrench to unscrew a bolt. That bolt loosened, [inside the disposer] will enable you to remove the whatever (Cloth, Sponge, Grease, Celery) is causing the clog.

If you do not have this 'Special Wrench' you are unlikely to find one at Lowes or Home Depot more than say: Ebay, listed as a 'Vintage Garbage Disposer Wrench'.

No sh*t, Ebay has everything.

You can try Mr. Plumber and other Degreasers (from Dollar Tree) but if it is a Sponge or Celery Strings or really caked on Grease You will more likely need to remove that bolt to get the worst of it out.

Just make sure it is unplugged before you start putting your hands in the Disposer.

I once saw on the TV show 1000 ways to Die some goon who drowned because their hair got caught in the disposer.

So, be careful.

Allen wrench is the tool you need a size that fits in little hole on bottom of disposal turn it once a full turn one way then back the other way a full turn. Push in reset button on bottom of disposal and turn it on by switch. Flush out with boiling water and some dishsoap. If it still isn't working then get thin bladed knife/butter knife(old one may wreck it) and run it along inside edge of disposal to dislodge anything stuck. This edge is inside disposal at bottom, around the outer edge there is small crevice where the ground up food and water flow out. it's really gross(of course gloves) but may need to feel around inside disposal to see if anything is jammed in crevice. Do it gently incase it's glass piece or metal something sharp that has been partially chewd up by disposal. Just make sure it's off!! even if you need to unplug(undersink) it while you check this crevice part. If I'm working on mine I have long wooden spoon(or something)with me so I can reach the reset button & the wall switch at same time to restart it.

If the reset button doesn't work for you after you have found if the disposal unit has something caught that is preventing the teeth from moving, or perhaps the pipe coming out of the disposal is plugged up, you may have burnt out the motor. Disposals don't last forever!