My boy did try to do it when he was about 1-1.5months. Neck strength not really there yet as need supporting, thus I will personally recommend not to let your baby do it. Gently coax them back if they’re trying around that age. Once he was about 3 months old or so when we observe he starts to have control of his head properly, we allowed him to try and flip all he wants to be proficient in flipping hahahaha. Now he’s unstoppable 😩