First, I can only confirm one fish is female, the one pointing upward on the right. You need to get a better photo of the anal fin area. The white fish is a molly while the other two are paltys. It could be a male and that is why it is behaving like that. They will interbreed. Get some better photos and I'll try to confirm for you.
Alo, how big is the tank? That could be part of the problem.
Alo, how big is the tank? That could be part of the problem.