DIAGNOSIS Yeah, this one's common. The compressor is running and the fan is blowing, but the refrigerant isn't cycling properly to create condensation. The most likely cause is the unit is low on refrigerant due to a slow leak, often from a factory weld or a vibrating connection.
FIX First, rule out simple stuff. Make sure the room is actually humid enough (above 45% relative humidity) and warm enough (above 65°F). If it is, and the coils inside aren't getting cold, it's a sealed system issue. For this model, that means a professional repair call to locate the leak, repair it, and recharge the system. It's not a DIY fix.
IF THAT DIDN'T WORK If the coils *are* getting very cold and frosted up but still no water, then the condensate pump (if you have that accessory) or the internal drain path is blocked. Check the drain hose for kinks and blow through the drain port on the back of the unit to clear any debris.
HEADS UP Be wary of any "recharge kit" sold online. This isn't a car AC system; it uses a specific type and amount of refrigerant (R410A), and improperly charging it can permanently damage the compressor. The repair cost often approaches the price of a new unit.