2.5 year old regressing in potty training ,stubborn and independent

We started potty training our daughter at 23.5 months old because she was showing interest about going on the potty. She ended up doing well and went to school for 3 months. She did well at school and progressed to not having accidents most days. We pulled her out beginning of July for a vacation and now she’s starting a new Montessori school closer to our house 8/15. Since July she’s had multiple accidents a day not everyday but way more than normal. We ask her why and she says she doesn’t want to hold it. We’ve gone back to rewarding her with chocolate everytime she goes on the potty and if she goes a full day without an accident, we give her ice cream at the end. We’ve tried having her pick out her favorite undies as well and told her we have to throw them away if she has an accident and have done so. I feel like we’ve tired everything and nothing seems to work. Shes very good at understanding things and reasoning but seems to not want to when it comes to going to the bathroom. Just looking for any tips or tricks that have worked or some new things to try, appreciate everyone’s suggestions:)