I had problems with acne on the upper back until I was 30 and found a solution. Here are some suggestions:
Get yourself a product including Salicylic acid. This costs like 10€ in a pharmacy and will last you some time. Personally I apply this while showering on my upper back but you could also use it similiar to a face wash, depending in your problem zone.
Then get you a prescribtion for a product including Zinc acetate as a topical. (at least you need a prescribtion for this in Europe). You could add zinc as a supplement (pills).
If this is not working (and I promise it will). You would have to go for harder stuff like retinol creme.