6 Month baby doesnt want to latch on

My baby is 6 Month she has been exclusive breastfeeding wver since she's born but suddenly she doesn't want to latch on with me and its alrd been 7 hrs , I was so worried, she just bite and pull and never even suck on it, In the end i had to give thru pump and bottle and she drink. Can anyone help to give explanation why ? I really want to latch on