Gentlease?

Kristen • Momma to my sweet baby boys Tommy Alan 07/01/18 Henry Garnet 10/04/20

I started my baby on Enfamil Neuropro Gentlease 2 days ago and ever since then he hasn't pooped and is very upset. I heard a lot of people saying how great this stuff is but so far I'm not seeing it. He is still extremely fussy and constipated. Anyone else?