It’s difficult to know what it is. I see a white semi-double peony, probably lactiflora, but there are very much of those. 2-3 feet high is average for most peonies, so that doesn’t help much. Could you provide some more information? Are the buds pink or white? Where was it obtained? Does it have sturdy stems or not? Are the flowers always semi-double or sometimes double as well? If I were to make a guess I would say ‘Minnie Shaylor’ (because of the red carpels), but I’m not completely sure.
All the best,
PS: I’ve moved your post to a new topic, it didn’t really fit as a reply to ‘how to post’.