Baby sleep so long

Hi can i ask. My 2month + baby boy he nowadays always slept so long. I dont know if i should wake him up like usual every 3hours or not. Because when he wokeup at 12am for his milk . Then he will sleep until 0530am. Its like more than 3hours .. do i need to wake him up or just wait for his call for milk? Quite worried uh as first time mummy . Coz lastime he use to wakeup every 2-3hours now like more than that.