Should I Use Carofit Cream To Get Rid Of Pigmentation?

hi,
Hi. I am 29 years old male.
I had developed black spot due to pimples 3-4 years ago.
Now for getting rid of it I went to dermatologist 15 days back.
He had given me some tablets of 20days and carofit ultra cream to apply at night.
From past 5-6 days I am applying the cream at night.
However after every 1-2 days I am observing a new black spots/pigmentation appearing on my face.
For how long one has to use the cream to get rid of black spots/pigmentation.
Should I continue using the cream. Eagerly waiting for your suggestion
Please help I am really worried