Night time struggles

Having the toughest time still with sleep. My LO will sleep 7p-5:30a waking only once to eat. And he will do that 2-3 nights in a row. Then he has 2-3 nights that are horrible. Waking every hour and needing to eat every 3 hours.

We are very consistent in his nighttime routine so I just don't get it 😫😫😩😩