Similac to enfamil

Ari

I switched from similac pro sensitive to enfamil gentlease and my girl went from drinking every 3-4 hours and slept 8 hours at night. Now on enfamil she is starving every 3 hours on the dot and continuing this into the night not staying asleep. She is also supposedly entering her third leap tomorrow. I was really enjoying getting sleep at night. Is it possible the enfamil isn’t as filling for her?