She likes to lick and pull the fur off the area of her nipples her back seems to bother her too its full of dandruff, what can I do to get her skin better again. I tried fish oil
You can check the quality of her fish oil. She may need a better source of omega 3 fatty acids. Consumer Labs has a listing of the proven label supplements.
For skin health, at least 20mg/kg EPA needs to be given daily for cats. Higher doses for cardiac/kidney/joint health.
Welactin in loose oil is easy to dispense onto their food. If you've already tried a good quality of omega 3 fatty acids for at least 4 weeks with no improvement of her coat, ensure she can reach the areas that have dander. Cats usually groom off shed skin with their very effective barbed tongue, but if she can't reach that area due to excess weight or neck/back pain, then she may need to lose weight or have her vertebral column assessed by a vet.