Most products on the Internet will only work for one skin type. There are no products which will work for both dark and light skin. I want to be able to say that I know for sure which products will help me, even though the manufacturers may not know for certain. Most products are based on an old formula which is not working well anymore. The most common problems are: 1. Too little product - Many people who use too much product for their skin are actually using too little product. 2. A small amount of product used in a large amount of time - This is not the case if you don't have an allergy. If you have allergies you should use less. You can try to use less for the first few times before trying to add more. 3. Too much product used together - This is the most common problem that people have. If you use more than one type of product at the same time, you will use more product than you thought you could. This can cause burning or even stinging on your skin. 4. The product that has all ingredients is not well tolerated - It is better to use only the product that you are allergic to.