@turquoise-- I think that niacinamide gel or cream is a hit or miss. It works for some people but doesn't work for others. It could also be the specific product you tried. I suggest trying a niacinamide cream with good reviews, you might get better results.
If niacinamide cream isn't working for you, there are other options for acne. One is zinc oxide cream. It can also dry up and prevent pimples and fade blemishes.