How relieve constipation ASAP on 15 mo old

Hi ladies, I need help! My baby gets constipated a lot. I give her fiber veggies consistently and I noticed that when I give her rice two days in a row she gets constipated really bad. She hurts when trying to pass the vowel movement. I’ve tried given prune juice but she doesn’t like it. I’ve tried feeding her black beans and it helps a bit, but she won’t eat much of it. I’ve tried the prune purée, but again, she won’t eat it.

Any other recommendations? As far as for food, maybe I’m doing this all wrong. Maybe I’m feeding her all bad stuff that causes constipation.