Are you getting it from just pills or naturally? 20 mins in the sun everyday is all you need to absorb Vitamin D (preferably shirtless). Vitamin A should be eaten via grass fed liver, pills are okay but are not healthy in the long run relative to liver.
Do you take magnesium supplements? Your acne gets worse on accuttane before it gets better so realistically the positive impacts of the supplements might have been outweighed by the fact you are on accuttane hence why it persists. You have to toughen out the course but when it’s ends keep looking after yourself.
forgot to mention it in the earlier post but if you are happy to part with $30, download clearskinforever. Actually really informative and helped solve all my acne. Wishing you the best anon. I been where you are, just have faith that it subsides one day