DIAGNOSIS You have correctly identified the pre-motor filter assembly. Improper cleaning or drying ruins suction and can damage the motor.
FIX Remove the dust cup. The filter assembly is behind it. Pull out the blue foam sleeve and the white felt filter behind it. Rinse both separately under lukewarm tap water until water runs clear. Do not use soap. Gently squeeze out water—do not wring or twist. Let them air-dry completely, away from heat, for a minimum of 24 hours. Reinsert the felt filter first, then the foam sleeve.
IF THAT DIDN'T WORK If suction is still poor after cleaning, the post-motor HEPA filter also requires attention. It is located at the back of the vacuum pod. Tap it gently to dislodge dust. Do not wash it. Replace it every 12-18 months under normal use.
HEADS UP Never run the vacuum with damp or wet filters. This forces dust into the motor and can cause immediate overheating and permanent damage. Always keep a spare dry filter set to swap in during the 24-hour drying period.