ok so try the ready to feed that doesn’t have corn- give it a full 2 weeks (every change needs 2 weeks for their ystems to adjust an for you to get a true picture of how they’re doing
if it’s not ‘too bad’ then consider adding in probiotics
if the ready tofeed just doesn’t work then try the baby’s care=- but the ready to feed is more broken down tI would imagine so I’d try that first if there isn’t any corn in it