Diaper changes & rashes..

I feel like every time my newborn poops there bum is pretty red and the sometimes has these small bumps which look kinda yeasty.. I’m constantly putting on a thick diaper rash cream to battle said rash or prevent it especially at night incase they sleep for a longer stretch. But no matter what I do it seems to always be there.. maybe because their poops are that runny consistency? A little thicker than pure liquid.. and an army green color. Anyone else battle this? He’s on a gentle formula to begin with.. not sure what to do.