It seems that you may be having stomatitis
There may be some cause.
Vitamin and nutritional deficiencies,anaemia,immunocompromised conditions, viral diseases,drugs..may be responsible.
You consult dermatologist
or oral surgeon.
Investigations may be done to find out the cause.
Oral vitamins,immunobusters,antibiotics..etc may be taken.Betadine
gargles may be done to improve oral hygiene
Oral paste containing steroid may be helpful.
You may be improved.
I hope you got my answer.
Dr. Ilyas Patel MD