A vacuum cleaner losing suction power is usually caused by clogged filters, a full dustbin, or blockages in the hose. Empty the dustbin regularly and clean or replace the filters as recommended by the manufacturer. Check the hose for debris, as large objects can get stuck and restrict airflow. Also, inspect the brush roll for tangled hair or dirt buildup. If the vacuum still doesn’t work efficiently, ensure there are no air leaks in the hose or connections. Regular maintenance will keep your vacuum cleaner performing well and improve its lifespan.