How do i get my baby to nurse longer?

My baby is 6 says old. Since birth she’s had a great latch and was nursing each side for 10-15 minutes. Over the last few day’s she’s been cluster feeding. She’ll sleep for a few hours. I’ll nurse her. She’ll nurse for a few minutes and then fall asleep on the boob. When I take her off to burp her she freaks out. As soon as I latch her again. She’ll nurse for another minute and then fall back asleep. How do I encourage my baby to nurse for longer stretches?