A member from WV has had success planting deep . Maybe he will see this post and comment. It could be its not getting enough water down to the root ball or too much standing water at the root ball. Either is bad for it. Maybe replant it and bring it up to ground level. If you want a large plant, Increase the hole size and mound it up with good loomy mulch. Just my opinion from observation of my own and others across the state is they will grow but not as well in natural soil. Prep/amend the soil with good organic mulch and enlarge the hole to give it room to grow and expand. You can cover to protect in winter.

Thanks but my goal is to plant them deep and not have to worry about protection. I have seen many posts about people doing this and their plants grow very well, however I do not really see specific topics on anyone having trouble with this or perhaps what type of soild to use. I think I will take ur advice and pull it out, ammend the soil better and make the hole larger, then replant deep again.