Little one decided not to sleep at night anymore

My 1 month old has been sleeping great! But all of a sudden he wakes up at 1am and will not go back to sleep till 4am. He will fall asleep while I breastfeed no matter how hard I try to keep him awake, but as soon as I lay him down he wakes up and cries unless we pick him back up. He's a lazy baby bc if I pump and feed via bottle or give formula he will drink it all then fall asleep. But still wake up when I put him in his bassinet. He'll fall asleep instantly if I keep him in bed next to me. Any tips?! I do not want to continue having him sleep in the bed with us! Thanks!