Sttn is a milestone, different babies will do it without intervention at their own pace. Mine still wakes up a few times at 13 months. You can intervene by sleep training if it's bothering you too much, but if you can deal with it then it's better for baby to get there on his own when he's ready :)
You can try sleep training! But if your lo is waking up for milk and not just to fuss, maybe your lo is not ready yet. All the best! Each and every baby is different. Some babies can sttn from 1 month old, while some 11 month old babies are still waking up for milk. Don’t stress too much!
Donutella