My son lately has been waking up at like 2 am and then waking up consistently every 30 mins after…

My son lately has been waking up at like 2 am and then waking up consistently every 30 mins after that until the morning. All we have to do is put his pacifier back in his mouth and he goes right back to sleep but then he still wakes up 30 mins later again. Idk if he's hungry or what I should do?? Have any of y'all put rice cereal in the bottle at night to help them stay asleep longer?? I'm considering that but I want feedback first