Hello 👋
Only coconut won't help to remove pigmentation completely additional medications are needed to reduce pigmentation
Detailed history and examination along with clear pictures are needed for further evaluation and management
Lip darkening and dryness could be due to various causes like
vitamin deficiency, habitual, habits, chronic exposure time , contact dermatitis, reaction
Various treatment modalities are available depending on site and severity of condition
Next Steps
do consult online Dermatologist for better cosmetic results