At best, a proof of concept of experimental delivery drones exist, but only for small, lightweight items, and only in a few places, only in the right weather, and only if you place a target on your driveway and are there to receive the item in person, and all at the cost of a very high noise level. That's not exactly a real service.
You are sort of moving the goal post. The fact remains, drone delivery exists and is a solved problem. Major metro areas like Dallas, Texas have it through retailers like Walmart. Just because it does not meet your specific goal post does not mean it's a proof of concept.
