Sucking up liquid

check the tank lid. It is very common for people to install the lid and not engage the front tabs that hold the lid in place at the front. The lid must be fully down on the tank for suction to get to the floor. Try to lift the front of the lid. If it comes up slightly, then it is not properly attached. Also, make sure that the removable duct is in place. You remove it to use the hose and replace it to go back to floor.