Looks like thrush go to the dr they will give u medicine u rub on it with a q tip and u need to boil every thing that goes in her mouth (bottle Nipples, toys, pacis) my daughter had it they said she got it cause I was on antibiotics during birth idk 🤷🏼♀️
It’s thrush call the pediatrician they will prescribe drops that will clear it up in no time , I have seen way worse cases if u catch it now she should clear up fast.
Its not serious dont worry. Its just like a fungus or yeast not sure which one 🤔. My oldest son got it when he was a baby. If your bottle feeding boil bottles and make sue they are cleaned after every use. If breastfeeding just clean you nipple before feedings and after . Ooh to help it clear up just get a cloth and warm water an lightly rub . I did it twice a day Or you can go to the doctor they may give you oral drops that help