Unfortunately, it sounds like you are suffering from skin hypopigmentation, which is a potential complication of laser skin treatments. It is more common in those with darker skin tones. Essentially, it results from inflammatory changes in the skin that occur after the laser treatment which result in gradual loss of pigmented cells from the treated areas.
You do not mention when you had the laser treatment done, so these skin color changes may still be evolving if this was a recent procedure. If so, the most important thing for you to do is to protect the skin, especially from the sun. You should avoid direct sunlight at all times and where sunscreen whenever outdoors. This may help to limit the degree of color change that develops.
Unfortunately, hypopigmentation after laser treatment is a complication of this type of treatment that often does not improve. If it has been a while since your treatment and you have not seen any improvement, you should go to see your dermatologist
. In some cases, certain creams may help to smooth out the color changes but, generally speaking, this is a problem that tends to be persistent and not improve very much after the initial healing period.