Hi there....
A photograph would be of big help in this instance!!
Since it's on both 'Chicks' as per your description, it is more likely to be a condition we term Melasma.
A more detailed history and information is required including details of your medical history, personal history etc to help make a proper assessment and offer a clear treatment path.
There is nothing to stress of worry about.
Should be easily sorted.
Don't know how accessible a Dermatologist 's Clinic is to you ... You can possibly consider an INSTANT Consultation or an ONLINE Consultation for best outcomes 🙏
Health Tips
Avoid OTC products and home remedies