Is my fraxel dual 1550:1927 treatment working for my PIH from an IPL laser?

Thank you for your question and posting pictures.  Your skin is too dark to have ever considered an IPL treatment.  It looks and sounds like you might have Post Inflammatory Hyperpigmentation (PIH).  You can start by looking for prescription strength 4% Hydroquinone (HQ) to reduce the pigment.  Do not buy it over the counter or off the internet.  Laws vary by state.  In Texas, physicians can prescribe and dispense in office.  We have been very successful using the PicoSure laser with the FOCUS and / or Flat Lenses eliminating hyperpigmentation with a series of treatments.  You will probably have to travel to Houston to find a PicoSure.
FOCUS lens treatments have the extra benefit of reducing the underlying scar tissue.  This is one of our go to treatments for patients older than 40 and worried about the signs of aging.  This laser is safe for all skin types.  Start with sunscreen every day!  Once you have treated your hyperpigmentation to your satisfaction, you will probably need a follow treatment every 6 to 12 months depending your level of re-pigmentation.  Best of luck.

Agree that HQ is the base medical treatment, along with SPF. Follow up documentation with your dermatologist can give an unbiased opinion in regards to laser therapy. 1927 can be effective in reducing PIH and side effects of IPL, however given the clinical picture, the location and your skin type, you will require between 4-8 sessions over one year or so for optimal outcomes. Dr Davin S. Lim, Brisbane. Australia.