This almost exact thing happened with me with a hiking app I used to make. We had a 7-day trial when you started the app, but we shipped a release that broke this and made all the paid features immediately paywalled. This led to a big increase in sales and we got rid of the trial forever.
It’s possible that our trial might have worked better if it were like modern iOS trials that start charging you after a certain period, but ours just let you use the paid features for 7 days and then lapsed, and it stifled sales. My theory was people urgently needed the paid features (mostly to download maps for a coming trip) so the trial got in the way of them paying right away.