I went through it all I went through a breast strike and teething all at once so I had to use nipple shield and different positions for her so I know you’re probably doing your best and I promise you it does get better. My baby now is seven months and feeds like a champ.
Not sure if you give the baby a bottle, but if you feel that your baby is not feeding enough, and you do have a letdown and collect it you can offer them that extra milk but regardless, I’ve noticed that if they don’t feed enough the first time they’ll definitely come back within 45 minutes to an hour
At four months, my baby also struggled with feeding positions. It does get better. They’re just learning their environment and bodies. I recommend sitting the baby right beside you and holding their head and then it sounds kind of weird but laying the baby down or propped up and you getting on top of them almost like a bottle at this point, you’ll have to minimize any distractions to help out with the baby feeding, but the baby will cluster feed if they don’t feed the first time so just watch for hungry cues