My 3months old daughter allnof sudden dosent want to sleep on her back.the moment I lay her down she wakes up but sleeps comfortably when J put her on her tummy.why is this happening?

A. J put one of her tummy that I’m not understanding but sometimes kids like to sleep on the side position will make your child sleep on the right or left if the child is not interested in sleeping on the back that is completely alright different positions are anyways good to be slept in