Probably the air conditioner is tilted a LITTLE into the room (it should be tilted back a bit and has to be HORIZONTALLY level). In some brands of air conditioner, there is only ONE channel, on ONE side of the air conditioner that passes the condensate that drips from the fins to the back of the air conditioner where it evaporates (or drips out).
If the air conditioner is tilted forward OR horizontally AWAY from that channel, water stays in the little catch basin in the front of the fins. As it builds up, it can spill into the area where the fan is sucking cold air and blowing it into the room.
Sometimes lint or a bug gets caught in the channel and that stops water from getting to the back. Unclog the channel by flushing it out water (aimed away from all electronics) or an air-compressor.
Sometimes the problem is in the BACK of the air conditioner. The evaporator pan fills up with water. Again, depending on angle, it might get so high or covered with algae that the fan can start picking it up and blow the water back into the room! Gross! Clean out the drip hole and/or the pan.