once he is able to flip back on his own then it will be fine! we all been thru that . for now.. just have to be careful and place a baby monitor near him so that you can hear him when he is whining. . and make sure he is not alone on the bed!
Give it some time when baby is able to flip back. For nights usually I swaddle hands and feet so my baby cannot flip over. He sttn at 2MO
May be use some pillow beside him to avoid turns .. we can’t monitor every-time , so better secure 1st
Safety should be the priority, bed guards or pillows around the baby ..