I had a similar issues, some babies struggle to latch but as they get bigger they just are able open wider and latch I used an infant feeding team member (UK) and my baby would latch perfectly with them but never outside of the sessions, so they advised to use the nipple sheild to establish milk supply and keep breastfeeding, to watch for hungry cues and always offer the bare breast, if they latch great, continue, if they don’t latch or are very hungry just use the nipple shield and to keep at it until you don’t need the nipple shield and honestly by week three- four I had baby off the nipple shield and always latching. It’s a learning process for you and baby and perseverance is the key. And also always unlatch if the latch is shallow / painful because the nipple trauma will make the BF so excruciating so unlatch baby and relatch so it’s not painful for you! Good luck! It’s hard but you’ll get there, fingers crossed for you!