Spit Up Help

P

I have a 14 week old baby who is primarily breastfed with maybe 2 or 3 bottles a day. This past week her spit up issues have returned. I put her in the breast and when she gets fussy I burp her before switching to other breast. However lately, she is spitting up what appears to be the entire feed. This isn’t happening when I give her bottles. She does not have any ties and I have tried multiple different positions (cradle, side lying, koala). Has anyone else experienced this? I have worked with a Lactation Consultant who says it’s an over active letdown. However, the spit up amount is insane. Plus she isn’t pooping daily anymore either. Any help would be appreciated!