Potty Train

My Havanese is 16 months old and is very inconsistent when it comes to using the potty outside. She never really goes potty in the house during the day, it’s only at night. It’s not every night, just random nights. Every time she does it in the house she knows she’s in trouble so I don’t understand why she continues. I feel like I’ve tried everything and have no clue what to do. We take her water up at 7:00 PM and always let her out multiple times before bed. Any tips?