Hello and hope you are doing well.
Vitamin deficiency can cause symptoms of glossitis, tongue inflammation and stomatitis. The other causes could be due to fungal infection or rash. It could also be canker sores. You will need to consult your dentist who will examine you and determine the cause so that appropriate therapy can be initiated. In the meantime, take OTC multivitamins rich in riboflavin to counter the mouth ulcers.
Hope this helped and do keep us posted.