6 week old feeding issue

so baby is 6 weeks old, born at 34 weeks so she will be 40 weeks corrected tomorrow.

she has been feeding from a bottle since she was born. the beginning of her feeds start great, she has a good suck swallow breath rhythm. then once we take the bottle away and burp her, then give the bottle back to her, she starts this weird “gulping” it sounds like and milk starts to leak out of her mouth, or she chokes on it. and once she starts that she doesn’t stop.

i’ve tried changing nipples, supporting her chin, making sure her tongue is down, i’m not sure if there’s anything else i can do?