We can try and help you out here, and there's a number of possible issues, but the first thing you'll want to do is use the hand crank to make sure the jack can raise, as this will tell you if there is an issue with the gears being stripped or damaged on the Electric Jack # EJ-3520-BBX.
If you can't get the jack to go up with the hand crank, that means the gears have been damaged and it will need to be replaced with either the Black # EJ-3520-BBX or White # EJ-3520-WBX.
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