Tigerlily.. home remedies do work but they take a long time
I suggest u're derm and maybe he/she wud be able to prescribe u topical lightening creams/gels.
A home-remedy is red sandalwood powder, wild turmeric and lemon juice (enuff to make a paste) leave it on for 1/2 hour and wash-off
Saffron oil is also known to fade acne marks.