You approach your dermatologist again. And follow his instructions. If that is not possible, then apply Suncross sunscreen 15 min before going out and repeat 3 hourly (e.g. 9am, 12 noon, 3pm). Apply biluma all over face, more on dark spots, in the evening and scar-end cream on scar area at night. This is general protocol and varies from patient to patient depending upon the problem. So better meet you dermatologist again.