If your device is turned on but won’t suck anything up, try emptying your dust cap of any debris regularly or replacing it if it is very old. Also check to see if there’s is any build up in the vacuum tube by turning off the device and checking with a flashlight. If you find anything, just use a long and dull stick to remove it. If the problem persists you may have a tear in your vacuum hole, so follow the guides to remove it.