Shredder was shredding paper and the shredder stop will not work on auto or reverse

If the motor will not run, then probably there's paper clogged in the shredder. Turn over the shredder, after unplugging the power cord, and remove the papers.

If the motor will run but not shredding any paper, then the drive gear has broken teeth. This is not usually worth fixing.
Hope this helps.

Check the Power Ensure that the shredder top is firmly placed in the shredder basket if the unit will not operate. If the top is not in place the feeder will not work and accept any paper. Make sure it is firmly plugged into the wall outlet and that the outlet is active. Rest the Shredder Let the shredder cool down if the shredder has been running continuously for a long time. It may have overheated and needs to be left in the off position for at least 30 minutes to reset. Verify the basket is empty or not too full as that will cause the shredder to deactivate. Clear Paper Jam Rotate the shredder into "Auto" and reverse to loosen any paper jam that is stopping the gears. Pull out any papers that are sticking out from the shredder feeder. If there is no progress then unplug the shredder and remove the shredder top from the bin. Turn it upside down and use tweezers to free any paper that is blocking the gear. Auto Mode Not Working Select the "Auto" option and feed paper into the center of the feeder tray if the shredder is only working in reverse mode. The sensor is located in the middle of the feeder tray and could be blocked by jammed paper. Use an index card to firmly unblock any paper that could be blocking the sensor.

I got mine to work by running it on reverse for a moment then sliding it to auto. It stopped. Then I did it again. This time auto ran just for a second then stopped. I did it a third time but I had a sheet of paper ready in the feeder. Ran on reverse. Slid it to auto and it took the paper and shred it. I did it a fourth time. Reverse slide auto and feed shred the paper. Fifth time Auto shred the paper without reverse. :)

Might be:
Paper too thick,
Too many sheets,
Shredder blades blunt.
Also head between blades for obstructions.

Continue to alternate between auto and reverse a number of times. Try to shred narrower pieces of paper at opposite ends to see if it can trigger the auto trigger wire. All else fails, carefully take the shredding part apart and you may find a hugh paper jam underneath.

in the middle of the paper enterance clean sensor

Blow some canned air into the feed slot.

check and see if there is a jam of paper inside the unit or around the sensors

If you need further help, reach me via phone at https://www.6ya.com/expert/david_eb7ea98642566cc6

Shredder drive gear is probably shredded - hard part to find or replace usually. Could mean a new shredder;-(