Many people experience constipation on IP. I searched and did not see a dedicated thread for it, or a sticky for it. If this is a duplicate, I'm sorry.
There are many things to try for constipation:
Eat all your greens and veggies, and then add some free veggies.
Drink all your water and then add some more.
Drink Smooth Move Tea.
Miralax.
1000MG Vitamin C
Probiotics daily
Benefiber.
Extra Magnesium 500 to 1000 mg.
Patience.