Thanks for writing in.
can be due to postinflammatory changes.
Sun exposure can aggravate pigmentation.Keeping the sunprotection is important to treat hyperpigmentation. Use sunscreen with SPF 50.
My advise to you would be to use steroid based cream with moisturizer.
Also you can take vitamin C
tablets for hyperpigmentation.
Few treatments like peels,microdermabrasion
and fractional CO2 laser can help to spots effectively.
Consult a good dermatologist
who can provide you with these options along with effective oral prescription medicines.
Hope this helps.