DIAGNOSIS: That's the machine telling you it's either out of water or the water inlet is blocked. The blue LED is its status indicator for a water supply issue.
FIX: First, check the reservoir—make sure it's filled to the MAX line with cold water. If it is, the issue is likely in the inlet. Unplug the unit, pull out the reservoir, and check the small round filter screen on the bottom where it seats. It gets clogged with mineral deposits. Rinse it under warm water and gently scrub it with a soft brush or your finger to clear any gunk.
IF THAT DIDN'T WORK: The water pump itself might have failed or gotten an air lock. After refilling the reservoir, try tilting the whole machine forward about 45 degrees and then back to help prime the pump, then plug it back in.
HEADS UP: This model is picky about water quality. Using filtered water isn't just for taste—it seriously cuts down on these clogs and extends the life of the internal parts.