If you notice a loss of suction, your hose is likely clogged, or your filter needs a replacement. You can fix the clogged hose by pressing along the hose length to see if there’s a clog. (If there is, you can quickly feel it by hand). Now, press down on it and knead it to break it up into smaller pieces to go through the hose easier. A garden hose can also help to push out the clog. Even though I haven’t tried to use this method myself, many other vacuum users have said it’s helpful.