Welcome to the forum.
Black, cracked lips are indicative of hormonal
changes, increased iron level in blood, vitamin B deficiency
, biting/licking of lips, use of low quality lipsticks, lip balms, as a result of reaction to some chemical cosmetic, excessive intake of caffeine, addiction for alcohol, smoking
To help lips get better stop licking or biting them, avoid caffeine intake, stop all addictions, take plenty of water, take multivitamin
syrups mainly vitamin B complex, take fruits, berries, veggies, nutritious diet.
Keep lips moisturized, have a thorough health check up done and get treated well. Use good quality herbal lip products. Take care.