Funny, this is exactly what the FDA was telling me until they talked to our customers. They found out that according to our customers that our products did work and as a result of that the FDA stated that our products were rated as class III medical devices when sold for use on humans or animals or to treat or cure disease or illness. For that reason, we only sell them as experimental water treatment devices ( not for consumable water ).
So, you just used the wrong one or perhaps, you may not have used it properly.
Our zappers do not cure anything and do not heal. They only do one thing, they kill microbes such as bacteria, protozoa, fungi, etc.