Feeding issues - help

Maurice
Initially was on Cow & Gate first infant mill but baby kept on bringing up the bottle after almost every feed.
Tried comfort formula but had the same issue. Then moved onto the anti reflux one but was causing issues as well.
Went onto SMA stay down and that it did but she's not eating as much and when she does gets frustrated as the teats keep getting blocked and she falls asleep with the feed taking too long.
Any ideas on what I can do? The doctor has been as useful as a chocolate tea cup.
I just want the little one to get a decent feed that stays down and doesn't take more than 40 mins to get through.