Give yourself at least three months to start seeing progress with your post acne marks. Things will get better with time and patience (although I know how hard that can be). If you're still having issues with hyperpigmentation after your accutane course I would suggest you look into microneedling.

Apply nonfat buttermilk for 15 min
do every 2 days (gentle bleach)
apply tomatoes, strawberries, apples
do daily for 10-15 min( gentle bleach)