Potty accidents

My step daughter is still having frequent accidents at 3.5 years old. We’ve been potty training for over a year now. And it seems like it’s every time she comes back from her moms house for the longer part of our custody arrangement, it’s 50/50 but a 2-2-5-5 schedule. I’ve tried having her helping us clean up the poop when she does and she’ll stop until the next time we have her. We’ve tried giving treats when she goes on the potty but I feel she’s past that point. I’m just not sure what else to do! So what are your guys’ thoughts? And/or what did you do to potty train your LO