Witches and Pillagers no longer spawning

I have been in a creative world on bedrock on my iPhone and I just noticed that when I try to spawn pillagers or witches, they don't spawn at all. I tried doing /summon witch and /summon pillager and it says Unable to summon object. Every other mob I tried with spawn eggs and /summon do spawn.

 

How to reproduce

open up a creative world

try to use the witch and pillager using their spawn eggs

do /summon witch and /summon pillager

They will not spawn either way.