@SoapLover1 Unfortunately, boiling the water may kill bacteria, but will not remove the metals that cause rancidity or DOS.
Also, DOS is just one form or sign of rancidity. The soap can be rancid without any visual spots whatsoever. It may have only a bad smell, or the sweaty slickness. Whether accompanied by DOS or not, rancidity can be caused by using non-distilled water, rancid base oils, or rancid EOs - or from other factors such as storing in a damp location, in direct sunlight, or in contact with non-stainless metals.
@MicheleH besides refrigerating your EOs and base oils, are you able to purchase a countertop distilling machine? We have them available easily from Amazon here in the US, ranging from about $70US to a couple of hundred dollars. Here is a link to an example of what I am suggesting:
Countertop Distiller.