Hello, Welcome to health care magic
Scaling and dryness of lip (inflammation) is called cheilitis. There are a lot of causes of cheilitis. Our saliva is an irritant and constant licking can cause lip lick cheilitis. Vitamin B an iron deficiencies can cause cheilitis. Fungal infection
can cause chelitis and it is usually only over the angle of the mouth. Sunlight can cause actinic cheilitis
usually only over lower lip. Sometimes cosmetics including lip balm can cause contact dermatitis
In your case you mentioned that there are episodes of flare up with little bubbles under the skin. This is usually seen in herpes labialis which is a viral infection.
I recommend you consult a dermatologist
so that a diagnosis is made and you can be counselled according to diagnosis.
Hope this helped