Toilet problems away from home

My daughter will be 3 in a couple weeks. We started potty training last June. I had a baby in October and it caused a huge regression and we had to start over. After that she has been doing great. We still had her set on a timer to make sure she went when she should. A few weeks ago I took the timer away and just let her respond to her body when she had to go. I did this a few days at home and she did great! My mil keeps her during the day while I work. My mil took the timers away too and she’s not doing great at all at her house. She will have at least 2 accidents every day while she’s there and has none at home. We have no idea what to do in this situation. Does anyone have any tips or advice?