How do I get rid of black mold spots from my shower ceiling?

There were brownish mold spots on my shower ceiling and I used a mixture of bleach and water to remove them. Everything seemed fine but then the next morning, three little black spots appeared. I applied bleach to them, but they are not going away. I also tried vinegar and it was ineffective. Does anyone have any suggestions and/or know of any products that are effective? Thanks!