Platinum og(POG) planted in coast of main harbor b...

My guess would be overwatering. Do you have the clear cup sitting in the red cup with water to wick up? You don't want most plants to be sitting in water like that, especially small ones. Otherwise if you don't have drainage holes, you also probably have the roots sitting in too much water. The roots like air as much as water, let it drain and let the soil dry and the plant will hopefully slowly recover. It can take a while for oversaturated soil to dry, so be patient.