sleeping on tummy

Me
My daughter is 8 month old and is easily rolling around. When I put her to sleep, I put her on her back, but for past couple of days I find her sleeping on her belly. I flipped her back about 6 times at night and still found her on her belly. She sleeps in her crib in a different room and I'm terrified 😳 is she safe sleeping like that at this age?