You got yerself either a loose wire inside the enclosure or else something touching the power-supply positive post on the interior of the power jack, and causing it to short out. Open it up and you can probably find it. If its a shorting issue, just remove or relocate the cause of the short. If its a loose wire, you’ll see if. If you’re not sure where the loose wire goes post a gutshot with it in view and someone here can help you out. Pretty easy repair if you or a buddy can solder; if not lots of folks (me included) do pedal repair and can help you out.