Procreate on two ipads

I’ve been using procreate for years now on my iPad Pro. I recently got a new iPad mini and wanted to download the app on my new iPad. To my shock I had to purchase it even tho I was using the same ID on both devices. I requested refund on my mini and now I can’t update my procreate. So what’s happening because I googled if it can be downloaded on multi devices but it just didn’t appear on my purchased apps list on my iPad mini and it’s frustrating like ****.