It’s the teat that doesn’t seem right
What size teat are you using?
Newborn slow teat number 1
Sometimes if the bottom of the bottle or the lid is screwed too tight it doesn't work, might be worth checking that? 🙂I've had this issue so many times and it's usually down to suction. I also had to up the teat when i changed my boys milk as some is thicker than others
When I use the mam bottle. I usually measure them and put it in the breast milk bag. Then I use hot water to heat up the breast milk bag, so I know the temperature is just right and I put it in the bottle. I know that it takes a while to heat up when I put the milk in the mam bottle.